Review conversions and percent comp

How many grams are in 1.2 x 10²⁴ atoms of C?

• 29.34 grams

• 23.94 grams

• 6.02 grams

• 1.21 grams

Tags

NGSS.HS-PS1-7

What is the percent composition by mass of sulfur (S) in the compound MgSO₄?

• 20.22%

• 19.85%

• 26.64%

• 28.64%

Calculate the number of atoms in 0.0340 g Zn.

• 5.200 x 10^-4 atoms Zn
• 3.130 x 10²³ atoms Zn
• 3.130 x 10²⁰ atoms Zn
• 1 atom Zn

Tags

NGSS.HS-PS1-7

Determine the mass of 4.20 moles of C₆H₁₂

• 354 g

• 84 g

• 337 g

• 421 g

What is the molar mass of PbSO₄

• 303.3 g/mol
• 294.7g/mol
• 163.8g/mol
• 372g/mol

How many grams of NH₃ would result in 8 moles of NH_3. 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.

Which conversion factor should be used for the following question " How many molecules are there in 4.00 moles of glucose, C₆H₁₂O₆? 

• 1 mole = 78.12 g
• 1 mole = 22.4 L 
• 1 mol = 6.02x 10²³ particles 
• more than one

Which conversion factor should be used to solve the following, "How many moles in 28 grams of CO₂?"

• 1 mol = 22.4 L

• 1 mol = 44.0 g

• 1 mol = 6.02x10²³ atoms

• more than one

Find the percent composition of hydrogen in (NH₄)₂S.

• 11.8%
• 41.1%
• 47.1%

How many molecules are in 9.44 moles of Aluminum chloride?

• 5.68 molec AlCl₃

• 5.68x10²⁴ molec AlCl₃

• 0.705 molec AlCl₃

• 1.25x10²³ molec AlCl₃