Nitrogen makes up what part of the air?
3/5
2/5
4/5
About 4/5.
Hope this helps.
Answer: c
Explanation:
11. If two substances react and the temperature of the mixture decreases, the reaction
is a) Endothermic
b) Never going to happen unless it is heated
c) Exothermic
d) one that causes atoms to be destroyed
Answer:
a.endothermic reaction
The blood must keep moving round the body to keep the rate of diffusion high explains why
Answer:
red blood cells and diffusion.
Explanation:
this process involves red blood cells and diffusion. Red Blood cells (RBCs) are a type of blood cell whose role is to transport oxygen from the lungs to the peripheral tissues of the body. Oxygen diffuses from the alveoli of the lungs in to the RBC's, where it binds to hemoglobin.
Diffusion is a very important process within the human body and is essential to the transport of molecules within a number of organs including the lungs, kidneys, stomach and eyes. The lungs process millions of tiny air sacs that are called alveoli, each of which are in close contact with capillaries.
What mass of sulfuric acid, H2SO4, is required to react with 3.27 g of potassium hydroxide, KOH? The products of this reaction are potassium sulfate and water.
Have both the unbalanced and balanced chemical equations.
Explain how to find the molar mass of the compounds.
Explain how the balanced chemical equation is used to find the ratio of moles
Explain how many significant figures your answer needs to have.
The numerical answer
Answer:
pa help din ako jan pleaseAnswer:
Don't plagiarize here.
Explanation:
Your online teacher knows that you are looking here for the answer!!!!
What does the emission spectrum of a molecule show?
A. The energy the molecule absorbs as it undergoes a reaction to break down into its elements
B. The wavelengths of light a molecule gives off when an electron moves to lower energy levels
C. The wavelengths of light a molecule takes in when an electron moves to a higher energy level
D. The energy the elements give off as they undergo a reaction to form a molecule
Answer:
B. The wavelengths of light a molecule gives off when an electron moves to lower energy levels
Which of these describes why a stent is used?
A stent is a small mesh tube that holds open passages in the body, such as weak or narrow arteries.
Explanation:
To open an artery near the heart
just took the quiz
picture below
need done by 2:30
thanks, God bless your week
1. [tex]\sf \bf {\boxed {\mathbb {Evaporation}}}[/tex] - The changing of liquid to a gas.
2. [tex]\sf \bf {\boxed {\mathbb {Automobile}}}[/tex] - The major source of pollution.
3. [tex]\sf \bf {\boxed {\mathbb {Greenhouse \:effect}}}[/tex] - Carbon dioxide and water vapor trapping heat given off by Earth.
4. [tex]\sf \bf {\boxed {\mathbb {Ozonosphere}}}[/tex] - Layer absorbing ultraviolet rays.
5. [tex]\sf \bf {\boxed {\mathbb {Condensation}}}[/tex] - The changing of a gas to a liquid.
6. [tex]\sf \bf {\boxed {\mathbb {Ionosphere}}}[/tex] - Layer responsible for reflecting radio waves.
7. [tex]\sf \bf {\boxed {\mathbb {Troposphere}}}[/tex] - The layer in which weather changes.
[tex]\large\mathfrak{{\pmb{\underline{\orange{Mystique35 }}{\orange{❦}}}}}[/tex]
Answer:
1. Evaporation :- The changing of a liquid to a gas.
2. Automobile :- The major source of pollution.
3. Greenhouse effect :- Carbon dioxide and water vapour trapping heat gives off by Earth.
4. Ozonosphere :- Layer absorbing ultraviolet rays.
5. Condensation :- The changing of gas to a liquid.
6. Ionosphere :- Layer responsible for reflecting radio waves.
7. Troposphere :- The layer in which weather changes.
How does an atom behave if it has a full octet of valence electrons?
O A. It is very stable.
O B. It is very reactive.
O c. It is unpredictable.
O D. It is a gas.
Answer:
A) Very stable.
Explanation:
A valence electron ring takes up to 8 valence electrons. If it has full rings, it is stable.
How many grams are in 36.2 moles of Iron (I) fluoride?
Answer:
4084.808 grams (SigFigs: 4085 grams)
Explanation:
The molar mass of Iron fluoride is 112.84 g/mol.
To calculate the mass, multiply the molar mass by the number of moles.
36.2 mol * 112.84 g/mol = 4084.808 g
Convert to Sigfigs (if necessary):
4085 g
Answer:
The person above is correct
Explanation:
How do these momenta compare the ballon rocket?
How many moles of NaOH are present in 22.0 mL of 0.140 M NaOH?
Answer:
Mole of NaOH = 0.00308 mole
Explanation:
From the question given above, the following data were obtained:
Volume = 22 mL
Molarity = 0.140 M
Mole of NaOH =?
Next, we shall convert 22 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
22 mL = 22 mL × 1 L / 1000 mL
22 mL = 0.022 L
Finally, we shall determine the number of mole of NaOH in the solution. This can be obtained as shown below:
Volume = 0.022 L
Molarity = 0.140 M
Mole of NaOH =?
Molarity = mole / Volume
0.140 = Mole of NaOH / 0.022
Cross multiply
Mole of NaOH = 0.140 × 0.022
Mole of NaOH = 0.00308 mole
Thus, 0.00308 mole of NaOH is present in the solution.
Anhydrous aluminium chloride contain 20.2% by mass of aluminium show that the emprical formula for anhydrous aluminium chloride
Answer:(d) has a high melting point because it has a giant covalent structure ... (i) Calculate the maximum mass of propyl ethanoate that can be made from 7.20 g of ethanoic ... (c) Anhydrous aluminium chloride contains 20.2% by mass of aluminium. (i) Show that the empirical formula for anhydrous aluminium chloride is A
Explanation:
Hello, Flashligh explain where the energy comes from and how it is affecting change or putting an object in motion
Answer:
Our energy supply comes mainly from fossil fuels, with nuclear power and renewable sources rounding out the mix.
The energy associated with an object's motion is called kinetic energy. Kinetic energy is the energy of motion. All moving objects have kinetic energy
Explanation:
Answer:
Kinetic energy is the energy of motion. All moving objects have kinetic energy. When an object is in motion, it changes its position by moving in a direction: up, down, forward, or backward. As he winds up and releases the ball, the stored energy is changed into kinetic energy, the energy of motion!So that , energy comes from and how it is affecting change or putting an object in motion.
Explanation:
I ain't flashligh
Can someone pls help I need this quick
Zinc has been added to dilute sulphuric acid. The two react together and a gas bubble forms. The gas that forms is hydrogen. Prove why the gas is hydrogen.
Answer:
Here's your answer
Explanation:
When we insert a burning matchstick near the mouth of gas jar the matchstick burns with a pop sound and produces a blue flame. This proves that the gas collected is hydrogen.
hope it helps
4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems. a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)
Complete Question
4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems.
a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)
b) What is the pressure of the water column expressed in mm Hg (torr)? The density of mercury is 13.6 g/mL.
c) Calculate the pressure of the hydrogen gas above the water in the column.
d) Calculate the volume occupied by the hydrogen gas at STP.
Answer:
a) [tex]25\textdegree C=23.8 torrs[/tex]
b) [tex]P_w=758.8[/tex]
c) [tex]P_w=758.8=735torr[/tex]
d) [tex]V_2=20.82mL[/tex]
Explanation:
From the question we are told that:
Metal weight [tex]M_m=0.0713g[/tex]
Volume Hydrogen [tex]V_h=23.5mL[/tex]
Displace-ment Column of water 400 mm column of water
Temperature [tex]T =258\textdegree C[/tex]
Barometric Pressure [tex]p=758.8mmHg[/tex]
Vapour Pressure of water at [tex]25^oC[/tex]
Generally from (Consult Appendix E.)
a)
Va-pour Pressure of water at
[tex]25\textdegree C=23.8 torrs[/tex]
b)
Pressure of Water column
[tex]P_w=758.8[/tex]
c) Pressure of Water column (Consult Appendix E.)
[tex]P_w=758.8=735torr[/tex]
d)
Generally the equation for ideal gas is mathematically given by
[tex]\frac{p_1v_1}{T_1}=\frac{p_2v_2}{T_2}[/tex]
Therefore
[tex]V_2=\frac{p_1V_1T_2}{T_1p_2}[/tex]
[tex]V_2=\frac{735*23.5*273}{298*760}[/tex]
[tex]V_2=20.82mL[/tex]
List two possible steps where impurities may be gained, which would appear to be an increase in copper
yield (why you may get more than 100% of the copper back at the end). Be specific about the steps and
how they might add impurities.
Answer:
i) During washing
ii) During Measurement
Explanation:
The two possible steps are :
i) During washing : during the washing method the residue may be not completely dried out and this residue ( water) will add up to the final product ( copper yield ) and this kind of error is called human error.
ii) During measurement : If the weighing instrument is faulty there might be addition in value of the final copper yield which will see the final yield value > 100% . this error occurs when the initial value and final value is been weighed
What's the difference between a substance and a mixture
Answer:
a pure substance consists only of one element or one compound. a mixture consists of two or more different substances, not chemically joined together.
Explanation:
Radhe Radhe❤
Answer:
A pure substance consists of only one element or one compound. Whereas, a mixture consists of two or more different substances which aren't chemically joined together.
Question 1 of 10
What does a low number on the pH scale say about a solution?
O A. The solution is an acid,
O B. The solution is changing.
O C. The solution is a base.
O D. The solution sg neutral.
12. If a reaction is exothermic,
a) It takes more energy to break the bonds of the reactants than is released when the bonds in
the products are formed
b) More energy is released when the bonds in the products are formed than is used to break
the bonds in the reactants
c) The same amount of energy is used to break the bonds of the reactants as is
released when the bonds in the products are formed
d) The temperature goes down
Answer:
In the case of an exothermic reaction, the reactants are at a higher energy level as compared to the products, as shown below in the energy diagram. In other words, the products are more stable than the reactants. Overall Δ H ΔH ΔH for the reaction is negative, i.e., energy is released in the form of heat.
Explanation:
What kind of pattern can you see about elements in the same period with respect to electron
structures?
Answer: A pattern of same atomic orbitals can be seen about elements in the same period with respect to electron structures.
Explanation:
The horizontal rows in a period table are called periods.
Elements present in the same period will have same atomic orbitals.
For example, electronic distribution of Na is 2, 8, 1 and it is a third period element.
Similarly, electronic distribution of Cl is 2, 8, 7 and it is also a third period element.
Hence, both Na and Cl will have K, L, M shells, that is, they have three atomic orbitals.
Thus, we can conclude that a pattern of same atomic orbitals can be seen about elements in the same period with respect to electron structures.
A student added magnesium hydroxide to a solution of hydrochloric acid. What is the
correct balanced chemical equation?
Answer:
bleh
Explanation:
Neutralization reaction between magnesium hydroxide and hydrochloric acid Mg(OH)2(s) + 2HCl(aq) → 2H2O(l) + MgCl2(aq) b.
so uh pretty sure Mg(OH)2(s) + 2HCl(aq) → 2H2O(l) + MgCl2(aq) b.
correct me if im wrong <3
what do you mean by chemical reaction
Answer:
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products.
A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Chemical reactions are an integral part of technology, of culture, and indeed of life itself. Burning fuels, smelting iron, making glass and pottery, brewing beer, and making wine and cheese are among many examples of activities incorporating chemical reactions that have been known and used for thousands of years. Chemical reactions abound in the geology of Earth, in the atmosphere and oceans, and in a vast array of complicated processes that occur in all living systems.
Explanation:
hope it help
plss brainlys me
Answer:
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products
Explanation:
Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Gas occupies 30 Liters at 2.0 atm pressure and 27° Celsius. How many moles of gas are present
identify if it is mixture,compound or element
Answer:
12:35
Try it this way. egst11245
Answer:
A is mixture
B and C are compund
D and E are elements
F is also mixture
State the name(s) of the sub-atomic particle(s) that have/has a positive charge. Answer with the name of the particle(s) only.
A. Neurons
B. Protons
C. Electrons
Answer:
protons because they have the most positive charge
You have 2.7 moles of carbon. How many atoms do you have?
Answer:
1.63 × 10²⁴ atoms.
Explanation:
To calculate the number of atoms (N) contained in 2.7moles of carbon, we multiply the number of moles (n) by Avogadro's number (6.02 × 10²³).
That is, N = n × nA
Where;
N = number of atoms
n = number of moles (mol)
nA = Avogadro's numbe
N = 2.7 × 6.02 × 10²³
N = 16.254 × 10²³
N = 1.63 × 10²⁴ atoms.
Hence, there are 1.63 × 10²⁴ atoms in 2.7moles of Carbon.
why elements with more than 20 protons always have a more neutrons than protons?
Answer:
Elements that have atomic numbers from 20 to 83 are heavy elements, therefore the ratio is different. The ratio is 1.5:1, the reason for this difference is because of the repulsive force between protons: the stronger the repulsion force, the more neutrons are needed to stabilize the nuclei.
PEASE RESPOND QUICKLY WILL GIVE BRAINLIST!!!!!!!!
Which of the following polyatomic ions will form an ionic compound with a single sodium ion? (5 points)
A.)CO32−
B.)PO43−
C.)SO42−
D.)NO31−
Answer:
D).
[tex]{ \tt{NO_{3} {}^{ - } }}[/tex]
Explanation:
The nitrate ion because it is a radical with a valence of 1, forming sodium nitrate.
[tex]{ \tt{Na {}^{ + } .NO _{3} {}^{ - } }}[/tex]
The polyatomic ion that does form an ionic compound with a single sodium ion (Na^+) is NO3^- .
A polyatomic ion is an ion that contains more than one atom. Recall that an ion is any chemical specie that contains a positive or negative charge. Sodium is a member of group 1 and forms a univalent positive ion.
The polyatomic ion that does form an ionic compound with a single sodium ion (Na^+) is NO3^- and the compound is NaNO3.
Learn more: https://brainly.com/question/8592296?
Arrange the compounds in order of increasing entropy (S).
CH3OH(s)
CH3OH(l),
CH3OH(g),
CH3CH2OH(g)
CH3OH(s) > CH3OH (l) > CH3OH(g) > CH3CH2OH(g)
CH3OH(s) < CH3OH (l) < CH3OH(g) < CH3CH2OH(g)
3 Of 20
Answer:
CH3OH(s)<CH3OH(l)<CH3OH(g)<CH3CH2OH(g)
Explanation:
Entropy is defined as the degree of disorderliness of a system. The more orderly a system is, the more its entropy tends to zero.
Hence solid particles have the least entropy because solid particles do not translate. The entropy of liquid particles is greater than that of solid particles since liquid particles can translate. Gas particles have the highest entropy because gas particles move at a very high velocity owing to minimal intermolecular interaction.
Also, the heavier the molecules of a substance, the larger its molar entropy therefore, CH3CH2OH(g) exhibits the greatest entropy.
Which particles are attracted as a result of the electrostatic force?
A. Protons and electrons
B. Any particles that have mass
C. Any particles that have like charges
D. Protons and neutrons
Answer:
A. Protons and electrons