Answer:
Mole Fraction = 0.059
Explanation:
To find the mole fraction, you need to (1) convert grams H₂SO₄ and H₂O to moles (via molar mass) and then (2) calculate the mole fraction.
(Step 1)
Molar Mass (H₂SO₄): 98 g/mol
34 grams H₂SO₄ 1 mole
-------------------------- x ------------------- = 0.347 moles H₂SO₄
98 grams
Molar Mass (H₂O): 18 g/mol
100 grams H₂O 1 mole
------------------------- x -------------------- = 5.56 moles H₂O
18 grams
(Step 2)
moles solute
Mole Fraction = -------------------------------------------------
moles solute + moles solvent
0.347 moles H₂SO₄
Mole Fraction = -----------------------------------------------------------
0.347 moles H₂SO₄ + 5.56 moles H₂O
Mole Fraction = 0.059
When Aluminum oxide is heated with iron no reaction takes place?
Answer:
Explanation:
That's correct. Once Aluminum becomes an ion, it is very hard to force it to take back its electrons. Only a few elements can do it. Iron is not one of them.
Can someone help with this one?
what is the hardest part of the periodic table?
Answer:
carbon
Explanation:
I hope this helps :)
Answer:
carbon
Explanation:
YOU CAN MARK ME AS BRAINIEST IF YOU WANT
ontrast the mechanisms of the following two reactions, the dehydration and condensation of ethanol. Part A The first step of dehydration of ethanol is _______. The first step of condensation of ethanol is ________. The first step of dehydration of ethanol is _______. The first step of condensation of ethanol is ________. protonation, deprotonation protonation, protonation deprotonation, protonation deprotonation, deprotonation Request Answer Part B Dehydration of ethanol is __________, condensation of ethanol is __________. Dehydration of ethanol is __________, condensation of ethanol is __________. a substitution, an elimination an elimination, a substitution a substitution, a substitution an elimination, an elimination Request Answer
Answer:
Part A: Protonation, Protonation
Part B: An elimination, A substitution
Explanation:
The dehydration ethanol and the condensation of ethanol all begin from the protonation of ethanol. This is because, water is a good leaving group. Thus, the protonation of the -OH moiety of the molecule is the first step in each mechanism.
The dehydration of ethanol is an elimination reaction because it involves the loss of H-O-H from the ethanol molecule while the condensation of ethanol is an substitution reaction because the -OH moiety is replaced by -OCH2CH3.
When a substance breaks up into two simpler substances, the reaction
is an)
reaction.
Answer:
Decomposition.
Explanation:
Decomposition Reactions T hose reactions in which a single substance (reactant) splits up into two or more simpler substances (products) are known as decomposition reactions. These reactions are carried out by supplying energy in form of heat, electricity or light which breaks that substance into simpler substances
I need help please my teaching is going to go crazy if I didn’t do it
Answer:
No One is going to answer all this because it hard to type it all in her. its easy to search it up
Explanation:
Define atmosphere and list any three ways in which
the atmosphere is useful for the survival of living
things.
Answer:
Explanation:
Atmosphere - the envolpoe of gasses sourounding the earth or another planet or the air in any particular place. The atmosphere protects us from the suns harmful rays, carrys cloud full of water so it can rain all over the world, and have oxygen, which is nessecary for survival to all living things.
Which substance below would have particles with the SLOWEST average velocity at 300 K?
Fluorine, F2
Chlorine, Cl2
Methane, CH4
Xenon, Xe
Answer:
Likely Xenon, [tex]\rm Xe[/tex].
Explanation:
The average kinetic energy of particles of a gas at a given temperature and pressure should be the same (regardless of the exact composition of the particle.)
For example, let [tex]m_1[/tex] and [tex]m_2[/tex] denote the mass of each particle of two gases, and let [tex]v_1[/tex] and [tex]v_2[/tex] denote the average speed of particles of each gas.
Average kinetic energy of particles of the first gas: [tex]\displaystyle {\rm KE_1} = \frac{1}{2}\, m_1 \cdot ({v_1})^{2}[/tex].
Average kinetic energy of particles of the second gas: [tex]\displaystyle {\rm KE_2} = \frac{1}{2}\, m_2 \cdot ({v_2})^{2}[/tex].
If the temperature of these two gases are the same, [tex]\rm KE_1 = KE_2[/tex]. Hence:
[tex]\displaystyle \frac{1}{2}\, m_1 \cdot ({v_1})^{2}= \frac{1}{2}\, m_2 \cdot ({v_2})^{2}[/tex].
[tex]\displaystyle \frac{v_1}{v_2} = \frac{\sqrt{m_2}}{\sqrt{m_1}}[/tex].
In other words, the average velocity of particles of each gas (at the same temperature and pressure) is inversely proportional to the square root of the mass of one particle of each gas.
Similarly, at the same temperature and pressure, particles of the four gases in this question would have the same average kinetic energy. However, the gas with the largest per-particle mass would have the slowest average velocity for its particles.
Look up the relative atomic mass of the particles:
[tex]\rm F[/tex]: [tex]18.998[/tex].[tex]\rm C[/tex]: [tex]12.011[/tex].[tex]\rm H[/tex]: [tex]1.008[/tex].[tex]\rm Cl[/tex]: [tex]35.45[/tex].[tex]\rm Xe[/tex]: [tex]131.293[/tex].Calculate the formula mass of each gas. That value would be proportional to the average mass of each particle of the gas:
[tex]\begin{aligned}M(\rm F_2) &= (2 \times 18.998)\; \rm g\cdot mol^{-1}\\ &= 37.996\; \rm g\cdot mol^{-1}\end{aligned}[/tex].[tex]\begin{aligned}M(\rm Cl_2) &= (2 \times 35.45)\; \rm g\cdot mol^{-1}\\ &= 70.90\; \rm g\cdot mol^{-1}\end{aligned}[/tex].[tex]\begin{aligned}M(\rm CH_4) &= (12.011 + 4 \times 1.008)\; \rm g\cdot mol^{-1}\\ &= 16.043\; \rm g\cdot mol^{-1}\end{aligned}[/tex].[tex]\begin{aligned}M(\rm Xe) &= 131.293\; \rm g \cdot mol^{-1}\end{aligned}[/tex].Among these four gases, each particle of xenon, [tex]\rm Xe[/tex], has the largest per-particle mass. Hence, at the same temperature and pressure, particles of Xenon would have the slowest average velocity among these gases.
20 POINTS! NEED HELP
How many electrons does sulfur have to gain to achieve the Octet Rule?
1. 1 electron
2. 2 electrons
3. 3 electrons
4. 4 electrons
Answer:
Sulfur needs 2 more electrons to achieve octet in its valence shell.
Explanation:
According to the electronic configuration, 2 electrons are required to be gained by the sulfur to achieve the octet rule.
What is electronic configuration?
Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.
Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.
Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.
Learn more about electronic configuration,here:
https://brainly.com/question/29757010
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Should vaccinations be required for students to attend public school?
Answer:
I don't think so for now, there hasn't been much research done with the vaccine and children so we really don't know how children's bodies will react to it. Once more studies are done with the vaccine and children and is proven safe then yes, kids should use it in order to attend public school.
Which term names an icy object that orbits the sun and has a tail?
meteorite
comet
meteor
asteroid
Answer:
Comets are small, icy objects that have very elliptical orbits. When they are close to the Sun, they form comas and tails, which glow and make the comet more visible.
Explanation:
Hope This Helps!!
(brainliest please, if possible)
Answer:
comet's
Explanation:
what the other user said
Circuit A has a resistance of 7.5 ohms, and circuit B has a resistance of 5 ohms. Which statement about the circuits must be correct?
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B
If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the
voltage in circuit B
If the current in circuit A is less than the current in circuit B, then the voltage in circuit A is less than the
voltage in circuit B
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the
current in circuit B
Answer:
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B
Explanation:
To know the the correct answer to the question, do the following:
Case 1: Let the circuit A and B have equal voltage say 24 V.
For Circuit A:
Voltage (V) = 24 V
Resistance (R) = 7.5 ohms
Current (I) =?
V = IR
24 = I × 7.5
Divide both side by 7.5
I = 24 / 7.5
I = 3.2 A
For Circuit B:
Voltage (V) = 24 V
Resistance (R) = 5 ohms
Current (I) =?
V = IR
24 = I × 5
Divide both side by 5
I = 24 / 5
I = 4.8 A
Thus for the same voltage, current in circuit A is less than the current in B.
Case 2: Let circuit A and B have equal current say 2 A
For circuit A:
Current (I) = 2 A
Resistance (R) = 7.5 ohms
Voltage (V) =?
V = IR
V = 2 × 7.5
V = 15 V
For Circuit B:
Current (I) = 2 A
Resistance (R) = 5 ohms
Voltage (V) =?
V = IR
V = 2 × 5
V = 10 V
Thus, for the same current, the voltage in circuit A is greater than the voltage in B
Case 3: Let circuit A have a current of 4 A and circuit B have a current of 5 A
For circuit A:
Current (I) = 4 A
Resistance (R) = 7.5 ohms
Voltage (V) =?
V = IR
V = 4 × 7.5
V = 30 V
For circuit B:
Current (I) = 5 A
Resistance (R) = 5 ohms
Voltage (V) =?
V = IR
V = 5 × 5
V = 25 V
Thus, when the current in circuit A is less than the current in circuit B, the voltage in circuit A is greater than the voltage in circuit B.
From the illustrations above and the options given in the question, the current answer is:
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B
How many molecules are in 17 grams of sodium chloride? Show your work.
Question 6
How many moles of carbon is found in 98.22g of carbon?
Answer:8.18 moles C
Explanation:
98.22g x 1 mole C/ 12.011g = 8.18 moles C
Which molecular compound is composed of the greatest number of atoms?
A. Carbon Dioxide
B. Dinitrogen Monoxide
C. Potassium Phosphide
D. Sodium Chloride
Answer:
Answer:
Potassium Nitride is composed of the greatest number of atoms.
Explanation:
find the number of atoms present in each compound we will write down their molecular formulas and then we will add up the number of atoms present in them.
A: Dinitrogen Monoxide:
Chemical formula of Dinitrogen Monoxide is N₂O. Therefore, it contains two atoms of Nitrogen and one atom of oxygen Hence, in total it contains 3 atoms.
B: Sodium Chloride:
Chemical formula of Sodium Chloride is NaCl. Therefore, it contains one atom of Sodium and one atom of Chlorine Hence, in total it contains 2 atoms.
C: Potassium Nitride:
Chemical formula of Dinitrogen Monoxide is K₃N. Therefore, it contains three atoms of Potassium and one atom of Nitrogen Hence, in total it contains 4 atoms.
D: Carbon Dioxide:
Chemical formula of Carbon Dioxide is CO₂. Therefore, it contains one atom of Carbon and two atoms of Oxygen Hence, in total it contains 3 atoms.
Explanation:
Find the total mass in kilograms of a ring that contains a 5.0 x 10 -1 carat diamond and 7.00 grams of gold.
Answer:
49 вот правильный ответ
Most of the sulfur used in the United States is chemically synthesized from hydrogen sulfide gas recovered from natural gas wells. In the first step of this synthesis, called Claus process, hydrogen sulfide gas is reacted with dioxygen gas to produce gaseous sulfur dioxide and water. Suppose a chemical engineer studying a new catalyst for the Claus reaction finds that 450 liters per second of dioxygen are consumed when the reaction is run at 264 degrees Celsius and 0.48 atm.
Required:
Calculate the rate at which sulfur dioxide is being produced. Give the answer in kg per second.
Answer:
[tex]0.21\ \text{kg/s}[/tex]
Explanation:
P = Pressure = [tex]0.48\ \text{atm}=0.48\times 101325\ \text{Pa}[/tex]
V = Volume = [tex]450\ \text{L/s}=450\times 10^{-3}\ \text{m}^3/\text{s}[/tex]
R = Gas constant = [tex]8.314\ \text{J/mol K}[/tex]
T = Temperature = [tex](264+273.15)\ \text{K}[/tex]
The reaction is
[tex]2H_2S+3O_2\rightarrow 2SO_2+2H_2O[/tex]
From ideal gas equation we have
[tex]PV=nRT\\\Rightarrow n=\dfrac{PV}{RT}\\\Rightarrow n=\dfrac{0.48\times101325\times 450\times 10^{-3}}{8.314\times (264+273.15)}\\\Rightarrow n=4.9\ \text{mol}[/tex]
Moles of [tex]SO_2[/tex] produced is
[tex]\dfrac{2}{3}\times 4.9=3.267\ \text{moles}[/tex]
Molar mass of [tex]SO_2[/tex] = 64.066 g/mol
Production rate is
[tex]3.267\times 64.066=209.3\ \text{g/s}=0.21\ \text{kg/s}[/tex]
The rate at which sulfur dioxide is being produced [tex]0.21\ \text{kg/s}[/tex].
Which is the formula for nitrogen trihydride? NH3 N3H 3NH N3H3
NH3
N3H
3NH
N3H3
Answer:
NH3
Explanation:
The "tri" attached to the trihydride means 3. So your hydrogen is going to have 3 atoms.
Answer:
All Answers only for the elite; Nomenclature of Covalent Compounds Quiz
You're Welcome :)
Explanation:
A-hydrochloric acid
B-sulfuric acid
C-dinitrogen pentoxide
C- IBr3
A- carbon dioxide
B- Start the name with hydro-.
B- H3BO3
C-sulfur trioxide
A- NH3
B- The chemical name ends with “hydroxide.”
Arsenate (AsO43-) is structurally and chemically similar to inorganic phosphate (PO43-), and many enzymes that act on phosphate will also use arsenate as a substrate if it is available. However, unlike phosphates, organic compounds of arsenate are kinetically unstable. For example, acyl phosphates (such as 1,3-bisphosphoglycerate) require an enzyme to catalyze phosphate hydrolysis on a biologically relevant timescale, but acyl arsenates hydrolyze almost instantaneously in water without an enzyme.
a) Predict the effect on the net reaction catalyzed by glyceraldehyde 3-phosphate dehydrogenase if phosphate were replaced by arsenate.
b) Write a balanced overall equation for the conversion of glucose to pyruvate in the presence of ATP, ADP, NAD+, and arsenate.
c) Arsenate is extremely toxic to most organisms. Based on your answers above, explain why.
Answer:
A) The effect on the net reaction catalyzed by glyceraldehyde is that
The 1-arsen0, 3-phosphoglycerate will decompose without enzymes hence no ATP will be formed in the reaction ( phosphoglycerate Kinase )
B) There will be no conversion of ADP to ATP from the conversion of glucose to pyruvate hence No balanced overall equation can be derived
C ) Arsenate is very toxic to most organisms and it is used mostly regarded as poisons during the formation of glycolysis, it forms 1-arsen0, 3-phosphoglycerate which hinders the formation of ATP because it is unstable and will hydrolyze quickly, this will also lead to the reduction in oxygen in cells thereby leading to the death of cells
Explanation:
A) The effect on the net reaction catalyzed by glyceraldehyde is that
The 1-arsen0, 3-phosphoglycerate will decompose without enzymes hence no ATP will be formed in the reaction ( phosphoglycerate Kinase )
B) There will be no conversion of ADP to ATP from the conversion of glucose to pyruvate hence No balanced overall equation can be derived
C ) Arsenate is very toxic to most organisms and it is mostly regarded as poisons during the formation of glycolysis, it forms 1-arsen0, 3-phosphoglycerate which hinders the formation of ATP because it is unstable and will hydrolyze quickly, this will also lead to the reduction in oxygen in cells thereby leading to the death of cells
Those structures that are similar in all behavior is called homologous structure.
The answer of the following question is as follows:-
The effect on the net reaction catalyzed by glyceraldehyde is that the 1-arsen0, 3-phosphoglycerate will decompose without enzymes hence no ATP will be formed in the reaction ( phosphoglycerate Kinase ) There will be no conversion of ADP to ATP from the conversion of glucose to pyruvate hence No balanced overall equation can be derived Arsenate is very toxic to most organisms and it is used mostly regarded as a poison during the formation of glycolysis, it forms 1-arsen0, 3-phosphoglycerate which hinders the formation of ATP because it is unstable and will hydrolyze quickly, this will also lead to the reduction in oxygen in cells thereby leading to the death of a cell.For more information, refer to the link:-
https://brainly.com/question/15804584
What type is hydropower?
Answer:
Hydroelectric energy, also called hydroelectricity or hydropower, is a form of energy that uses the power of flowing water to generate electricity. There are three main types of hydroelectric energy: impoundment, diversion, and pumped storage.
Explanation:
Consider the ranges of pitches made by these instruments and vocals.
A graph with frequency in Hertz on the x axis from 27 Hertz to 4166 Hertz. On the y axis are piccolo, oboe, flute, soprano vocal, violin, alto vocal, trumpet, clarinet, tenor vocal, bass vocal, guitar, french horn, bassoon, tuba, standup bass, bass guitar and pipe organ. Piccolo is 620 to 4166 Hertz, Oboe is 275 to 2200 Hertz, flute is 275 to 2200 Hertz, Soprano vocal is 200 to 1850 Hertz, violin is 196 to 3135 Hertz, alto vocal is 180 to 1760 Hertz, trumpet is 164 to 1050 Hertz, clarinet is 164 to 1900 Hertz, tenor vocal is 130 to 1306 Hertz, bass vocal is 96 to 987 Hertz, guitar is 83 to 850 Hertz, french horn is 83 to 1050 Hertz, bassoon is 61 to 529 Hertz, tuba is 49 to 246 Hertz, standup bass is 41 to 275 Hertz, bass guitar is 41 to 400 Hertz and pipe organ is 27 to 4166 Hertz.
In terms of the highest pitches they can make, which list correctly orders the instruments and vocals from highest to lowest?
clarinet, bassoon, piccolo, soprano vocal
piccolo, oboe, standup bass, tenor vocal
tuba, bass guitar, violin, piccolo
violin, clarinet, French horn, tuba
Answer:
D is correct
Explanation:
EDG 2021
Which of the following is a true statement about the Earths tectonic plates?
Answer:
Pretty sure it's C
Explanation:
Which event increases the amount of dissolved oxygen in the ocean water?
A. El Nino
B. La Nina
C. spring tides
D. Neap tides
Answer:
I think it is Ea Nino I may be wrong though dont hold me to it
The student recorded the mass of the cup + sample incorrectly and started with 2.20 g of hydrated compound but used 2.00 g in the calculations. Explain how this error will affect the calculation for the number of moles of water in the hydrate? Will the final answer be artificially high or low? How do you know?
Answer:
low
Explanation:
We were informed in the question that the student had incorrectly recorded the mass of cup + sample as 2.20 g but inadvertently used 2.00 g in the calculations.
This error will cause a slight decrease in the mass of water and ultimately decrease the number of moles of water in the hydrate.
What i am saying is that the number of moles of water obtained in the calculation will be artificially low.
Read each question carefully, and answer yes or no to each one. At the end of each section, follow the directions to score your answers (pay close attention as the directions for scoring may change for each section). After you complete the entire assessment, total the points from all seven sections. This will give you a total health score. The higher the score, the more healthy your lifestyle. If you feel you have a low score, look back through the assessment and identify areas where you can change your unhealthy habits, and explain what changes you would make and why. Write your assessment in the essay box below.
Section 1: Physical Fitness
Do you exercise or play a sport for at least 30 minutes three or more times a week?
Do you stretching before and after exercising?
Do you warm up before exercising and cool down afterwards?
Do you think that you are at a healthy weight?
Are you mostly happy with the way your body looks and feels?
Do you think you have enough energy?
Give yourself one point for each No response and two points for each Yes response. Section score: ____
Section 2: Family History
Do you have a family member who:
has high blood pressure?
has diabetes?
has heart disease?
has cancer?
is extremely overweight?
Give yourself one point for each Yes response and two points for each No response. Section score: ____
Section 3: Hygiene and Medical Care
Do you floss your teeth every day?
Do you brush your teeth at least twice a day?
Do you visit the dentist at least once a year?
Do you use sunscreen?
Do you know basic first aid?
Are all your immunizations current?
Do you get your vision and hearing checked each year?
Do you see the doctor for a check-up once each year?
Do you feel you get enough sleep at night?
Do you know the warning signs for cancer?
Give yourself one point for each No response and two points for each Yes response. Section score: ____
Section 4: Nutrition
Do you eat a lot of red meat or eggs?
Do you add salt to your food?
Do you add sugar to your food?
Do you eat a lot of high-fat or high-sugar foods?
Do you add butter or cheese to your food?
Do you choose fried foods more often than baked or broiled foods?
Do you drink caffeinated drinks, such as coffee or sodas?
Do you skip meals?
Give yourself one point for each Yes response and two points for each No response. Section score: ____
Section 5: Drug Use
Do you smoke or chew tobacco?
Do you drink alcohol?
Have you ever used marijuana or other illegal drugs?
Have you ever abused a prescription drug?
Give yourself zero points for each Yes response and two points for each No response. Section score: ____
Section 6: Safety
Have you ever ridden with drivers who were under the influence of alcohol or drugs?
Have you ever ridden with drivers who speed or disobey traffic laws?
Do you ever forget to wear your seat belt?
Do you ever forget to wear a helmet when riding a bike or skateboarding?
Do you ever play with matches or hazardous materials?
Is there a gun in your house?
Give yourself zero points for each Yes response and two points for each No response. Section score: ____
Section 7: Emotional and Social Health
Do you have hobbies or activities that you enjoy?
Do you give your best effort when doing your work?
Do you find it easy to laugh?
Do you express anger in an appropriate way?
Do you easily fall asleep at night?
Do you share personal problems with someone you trust?
Do you feel well liked by others?
Do you have someone you can turn to if you need help?
Are your family members and close friends in good health?
Are you generally happy?
Give yourself one point for each No response and two points for each Yes response. Section score: ____
Total Health Score: ____
Answer:
Yes
Yes
Yes
All yes
Explanation:
g As the number of nonvolatile solute particles in a given volume of solution increases, A) the boiling point increases and the vapor pressure at 25°C increases. B) the freezing point decreases and the vapor pressure at 25°C decreases. C) the freezing point increases and the vapor pressure at 25°C increases. D) the boiling point decreases and the vapor pressure at 25°C decreases. E) the freezing point increases and the vapor pressure at 25°C decreases.
Answer:
B) the freezing point decreases and the vapor pressure at 25°C decreases.
Explanation:
Colligative properties are those properties that depend on the amount of solute in solution. Both freezing point and vapour pressure are colligative properties.
As the number of nonvolatile solute particles increases, the freezing point of the solution decreases. This is known as freezing point depression.
Similarly, "Vapor pressure is a colligative property, so the vapor pressure of solutions is directly proportional to the amount of solute present in a solution. When a solute is present in a solvent, the vapor pressure is lowered because fewer solvent molecules are present at the top of the solution" (Lumen Learning).
Answer:
f u moderators
Explanation:
euurhtiuubbfjdhbgvzrbsf im sorry
What is the volume of 0.05 mol of neon gas at 1.45 atm and 275K?
Answer:
sdasdasddsafsadsfds
Explanation:
Is this answer correct
Answer:
Yes
Explanation:
Which phrase describes air density? increases as altitude increases Ο Ο Ο equals mass divided by volume pushes molecules in one direction exerts less pressure as it increases
♡︎PLS HELP IM TIMED PLS WILL GIVE BRAINLIEST!!!♡︎
Answer:
The correct answer is B. equals mass divided by volume
Answer:
They were right, I got all the questions right. If you need answers I got them I guess?
Explanation:
Which statement correctly describes atoms? *
-Atoms combine to make all the substances on Earth.
-Atoms of all substances have the same chemical properties.
-Atoms are easily destroyed when matter is cooled or heated.
-Atoms come in different sizes, but most are visible using a simple hand lens.
Answer: Atoms combine to make all the substances on Earth.
Explanation:
Atom is a smallest entity of any matter. The atoms of different elements combine together in order to form new substances. The atoms have electrons, neutrons, as well as protons. The atoms are combined by the chemical bond. When two or more atoms combine they form a molecule. The molecules combine to form compound. Atoms cannot be broken into sub parts. The two atoms of hydrogen and one of oxygen forms water which is an essential liquid on planet earth. Other substances like carbon dioxide, coal, and sodium chloride.