Given :
Number of He atoms, [tex]n = 3.4\times 10^{24}[/tex] atoms.
To Find :
How many grams are their in given number of He atoms.
Solution :
We know, molecular mass of He is 4 g. It means that their are [tex]6.022 \times 10^{23}[/tex] atoms in 4 g of He.
Let, number of gram He in [tex]3.4\times 10^{24}[/tex] atoms is x , so :
[tex]x = \dfrac{3.4\times 10^{24}}{6.022\times 10^{23}}\times 4\\\\x = $$22.58\ g[/tex]
Therefore, grams of He atoms is 22.58 g .
37 grams of H3PO4 ????
Answer:
76 grams is the correct answer to this question
PLEASE HELP WILL MARK BRAINLY
1. If a cube has 2cm sides and a mass of 10 g, what would it's density be?
A. 0.8 g/cm3
B. 1.25 kg
C. 1.25g/cm3
D. None of the above
2.If a cube has sides of 1.5 cm, and a mass of 15 g, would it float or sink in water?
A. float
B. Sink
3. A material with a melting point of 25C would be a solid at 15C?
A. True
B. False
4. A material with a Chemical Symbol of CO is an element.
A. True
B. False
Answer:magine 2 cubes. ... One cube is made out of gold and has a mass of 19.3 grams. ... Gold has a density of 19.3 grams per cubic centimeter, that is, 19.3 g/cm3 or 19.3 g cm-3 ... If you weigh 1.00 mL of liquid water it will have a mass of about 1 g so its ... They are both less dense than water so they will also float on top of water .
Explanation:
What must be done to calculate the enthalpy of reaction? Check all that apply. The first equation must be halved. The first equation must be reversed. The second equation must be halved. The second equation must be reversed. The third equation must be halved. The third equation must be reversed. What is the overall enthalpy of reaction? Delta.Hrxn = kJ
The overall enthalpy of the reaction has been obtained by reversing the second equation, and third equation must be halved. Thus, option D and E has been correct.
The complete reactions given in the question has been:
[tex]\rm C\;+\;O_2\;\rightarrow\;CO_2\\2\;CO\;+\;O_2\;\rightarrow\;2\;CO_2\\2\;H_2O\rightarrow\;2\;H_2\;+\;O_2[/tex]
The overall reaction has been:
[tex]\rm C\;+\;H_2O\;\rightarrow\;CO\;+\;H_2[/tex]
To obtain the overall enthalpy of the reaction, the intermediate reaction enthalpy has been arranged to give the overall equation.
The first equation has been in the correct sequence for the final reaction.
The second equation has been in in the same order to obtain the overall reaction. The CO has been the product, while carbon dioxide has been the reactant from equation 1. Thus, equation 2 has been reversed.
The third equation has 2 moles of water while the overall reaction has 1 mole of water. Thus, equation third has been halved.
Thus, to obtain the enthalpy of overall final reaction, the second equation must be reversed, and third equation must be halved. Thus, option D and E has been correct.
For more information about the enthalpy of reaction, refer to the link:
https://brainly.com/question/1657608
What must be done to calculate the enthalpy of reaction? Check all that apply.
The first equation must be halved.
The first equation must be reversed.
The second equation must be halved.
✔️ The second equation must be reversed.✔️ The third equation must be halved. ✔️ The third equation must be reversed.What is the overall enthalpy of reaction?
ΔH[tex]rxn[/tex]= ✔️131.3 kJ
If 9.87g of As2O3 reacts with carbon, then 7.71g of As should be produced. If only 6.33g of As is actually produced, what is the percent yield of As?
a 82.1%
b 0.821%
c 64.1%
d 0.641 %
Answer:
A
Explanation:
Percent yield= Actual yield/Theoretical yield x 100
The problem tells you that 6.33g of As is produced (actual yield), but 7.71g should be produced (theoretical yield). So 6.33/7.71= 0.821 x 100= 82.1%
Answer:
82.1%
Explanation:
A. I got it right on my test
responsible for bring messages from the sensory
organs to the brain. ?
A: Skeletal
B: Sensory
C: Motor
D: Axial
Answer:
motor nerves
Explanation:
sensory produces while motor transports
Explain the function of the nucleus, nucleolus, nuclear membrane, chromosomes, ribosomes, cytoplasm, cell membrane, mitochondria, Golgi complex, vacuole, endoplasmic reticulum, cell wall, chloroplast
Which unit is used for measuring atomic mass?
Answer: Amu
Explanation:
Help me!!
Question 5 only!
how many atoms are in 3N4010
Answer:
of N ( nitrogen): 12
of O (oxygen): 30
CHAPTER
CHAPTER ASSESSMENT
Understanding Main Ideas (Part A)
In the space at the left, write true if the statement is true; if the statement is false,
change the italicized term to make it true.
1. The overall charge of a formula unit for a compound is never zero.
2. In a crystal lattice, each positive ion is surrounded by negative ions.
3. Delocalized valence electrons are typical of ionic compounds.
4. A sulfate ion contains fewer oxygen atoms than a sulfite ion does.
true
5. Metals tend to be malleable and ductile and to have relatively high
melting points.
6. The more negative the lattice energy is, the stronger is the force of
attraction between the ions of an ionic compound.
7. In naming ionic compounds, the cation is named first.
8. When a metal reacts with a nonmetal, the metal tends to gain electrons.
9. In naming a monatomic anion, the suffix -ide is used.
10. The prefix per- is used in naming the anion with the most oxygen atoms.
Answer:
The answer is in correct
Why do scientific experiments need to be repeated?
A. Because scientists often make mistakes
B. To ensure that the same results are achieved every time
C. They only need to be repeated if the results are questionable
D. To discourage other scientists from trying to get the same results
Answer:
B
Explanation:
this is called peer review and your results will be stronger
8.
Sulfur trìoxide decomposes to sulfur dioxide and oxygen gas as
shown in the following reaction:
2503 (g) 2502 (g) + O2 (g)
Given a 240.0 g sample of sulfur trioxide (MM = 80.1 g/mol), how many
grams of oxygen (MM = 32.0 g/mol) are produced, assuming the
decomposition goes to completion?
g
Your answer should be rounded to three significant figures. Do not include units in your
answer
Mass of Oxygen : 47.9
Further explanationGiven
2S03 (g)⇒ 2S02 (g) + O2 (g)
240 g SO3
Required
mass of Oxygen
Solution
mol SO3 :
= 240 g : 80.1 g/mol
= 2.996
From the equation, mol O2 :
= 1/2 x mol SO3
= 1/2 x 2.996
= 1.498
mass O2 :
= 1.498 mol x 32 g/mol
= 47.9
Taking into account the reaction stoichiometry, given a 240.0 g sample of sulfur trioxide, 47.95 grams of oxygen are produced, assuming the decomposition goes to completion.
Reaction stoichiometryIn first place, the balanced reaction is:
2 SO₃ → 2 SO₂ + O₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
SO₃: 2 molesSO₂: 2 moles O₂: 1 moleThe molar mass of the compounds is:
SO₃: 80.1 g/moleSO₂: 64.1 g/mole O₂: 32 g/moleThen, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
SO₃: 2 moles ×80.1 g/mole= 160.2 gramsSO₂: 2 moles ×64.1 g/mole= 128.2 grams O₂: 1 mole ×32 g/mole= 32 gramsMass of oxygen producedThe following rule of three can be applied: if by reaction stoichiometry 160.2 grams of SO₃ form 32 grams of O₂, 240 grams of SO₃ form how much mass of O₂?
[tex]mass of O_{2} =\frac{240 grams of SO_{3}x 32 grams of O_{2} }{160.2grams of SO_{3}}[/tex]
mass of O₂= 47.94 grams
Given a 240.0 g sample of sulfur trioxide, 47.95 grams of oxygen are produced, assuming the decomposition goes to completion.
Learn more about the reaction stoichiometry:
brainly.com/question/24741074
brainly.com/question/24653699
Na * 6.02 * 10^23 pls help an it got to include na
Answer:
6.02E23Na
Explanation:
you just convert the element to a decimal form
Pb(NO3)2+K2CrO4 →PbrCrO4 +2KNO3 classify the chemical reaction
Which of the following do/does not change with the change in temperature?
i. Mole fraction.
ii. Molality.
Select one:
a. only i
b. Only ii
c. Both i & ii
d. Neither of them
(I did D and it was incorrect)
Answer:
c. Both i & ii
Explanation:
Moles do not change with temperature hence Mole fraction does not depends of temperature.
Molality is number of moles of solutes per kilogram of solvent. It has no relationship with temperature.
This means both of them do not change wit the change in temperature.
Correct option;
c. Both i & ii
What information is needed to determine a molecular formula
Answer:
Empirical formulas can be determined from the percent composition of a compound. In order to determine its molecular formula, it is necessary to know the molar mass of the compound. Chemists use an instrument called a mass spectrometer to determine the molar mass of compounds.
Answer:
The empirical formula and the molar mass.
Explanation:
AP3X
Which is Not part of hydrogen's line-emission spectrum?
Answer: Aufbau series.
Explanation:
HELP ME.
Convert 2.5 grams of water into molecules of water.
Answer:
1.5×1024 molecules
Good luck!
why do the properties of a material determine the use of the material?
Answer:
Matter is made up of particles whose properties determine the observable characteristics of matter and its reactivity.
Explanation:
Dominant genes are represented with lowercase letters while recessive genes are represented with capital letters.
1. True
2.False
Answer:
True
Explanation:
2. What is the molarity of a CuBr2 solution that contains 446 g of solute in 5000 mL of solution?
Answer:
0.4 M
Explanation:
M=moles/Liters
Convert grams to moles (446/223.37=1.99668711)
Convert 5000 mL to liters (5000/1000)
Plug in the values and solve
M=2/5
M=0.4
plzzzzzzzzzz help ASAP
Answer:
i think the answer is c because it says that is all they care
Air Pollution Quiz - Match the terms e defintions
1) Air pollution
2) Acid rain
3) Smog
4) Ground level ozone
5) Global warming
6) Greenhouse effect
Answer:
1) F. harmful gases and solid particles that enter the atmosphere
2) C. pollutant gases react with water vapor
3) B. mixture of smoke, gas, and fog
4) E. sunlight interacts with pollutant gases
5) A. gradual increase in the overall temperature of the earth
6) D. gases are trapped by heat and raise the temperature of the atmosphere
hope this helps
The shade or pigment of a mineral is known as
Luster
Hardness
Density
Streak
O Color
Answer:
Streak
Explanation:
The streak of a mineral is the color of the powder produced when it is dragged across an un-weathered surface.
please help i need to do good in this class
Answer:
Explanation:
di) number of protons is 12 for all, number of neutrons is 13 for mg- 25 and 14 for mg-26
The speed of chemical weathering depends on:
water freezing
amount of wind
soil depth
Answer:
Its soil depth
Explanation:
plzzzzzzzzzzzzz help me
Answer: omnivores
Explanation:
I just know
Look at the diagram below.
(+
When this atom becomes an ion, it will
(gain, lose)
electrons. The charge of this ion will be
Answer:
gain electrons
charge will be 4-
What is the electron configuration for an Atom that has 13 electrons
1 point
If the element Lithium (Li) were to bond with the element Sulfur (s), what
type of bond can you predict will be formed and why?*
A. Covalent-Li and S are two nonmetals
B. Covalent-Li is a metal and S is a nonmetal
C. Ionic-Li and S are two nonmetals
D. Ionic-Li is a metal and S is a nonmetal
Answer:
C. Ionic-Li and S are two nonmetals