16 questions
How many molecules are in 2.5 mol of NaCl?
1.50 x1024 molecules
1.50 molecules
4.15 molecules
1.51 x1024 molecules
How many moles are in 19.82 g Mg?
1.23 mol Mg
481.70 mol Mg
1.00 mol Mg
0.82 mol Mg
How many moles are in 3.01 x 1022 atoms of magnesium?
0.05 moles
1.81 x 1046 moles
5.00 x 1021 moles
5.00 moles
How many grams are in 1.2 x 1024 atoms of C?
29.34 grams
23.94 grams
6.02 grams
1.21 grams
What is the percent composition by mass of sulfur (S) in the compound MgSO4?
20.22%
19.85%
26.64%
28.64%
Determine the mass of 4.20 moles of C6H12
354 g
84 g
337 g
421 g
How many grams are in 1.2 moles of Neon?
0.05 grams
16.6 grams
21.2 grams
24 grams
How many hydrogen atoms are in one formula unit of C2H4O2?
2
1
4
6
Use the given the chemical equation to answer the following question:
2C2H6 + O2 → 4CO2 + 6H2O
What does the number 4 represent for the formula unit 4CO2 ?
The number 4 represents the coefficient, which is also equal to the number of grams of the formula unit above.
The number 4 represents the subscript, which is also equal to the number of moles of the formula unit above.
The number 4 represents the coefficient, which is also equal to the number of moles of the formula unit above.
The number 4 represents the subscript, which is also equal to the number of grams of the formula unit above.
How many grams of NH3 would result in 8 moles of NH3. What does the the number 8 do to the molar mass of the compound?
The number 8 is added to the molar mass to give 25 g/mol.
The number 8 multiplies the molar mass by 8 to give 136 g/mol.
The number 8 divides the molar mass by 8 to give 2.13 g/mol.
The number 8 does not change the molar mass of the compound.
What is the chemical formula for calcium carbonate?
Ca(CO)3
CaCO3
CaC3
Ca3(OH)
Which of the following methods should be used in order to calculate the molar mass of magnesium hydroxide?
Add the masses of two moles Mg to the mass of one mole OH
Add the total protons and neutrons.
Add the masses of one mole Mg to the mass of one mole OH
Add the masses of one mole Mg to the masses of two moles of OH.
A student calculated the number of moles of methane (CH4) present in a 100g sample of a gaseous mixture. If the student determined that there’s 0.6 moles of methane present in the sample, what is the percent composition of methane in the sample?
.096%
9.6%
.9%
90%