# Convert masses into moles for 1 and 2, convert moles into masses for 3 and 4.  Show all work1) 40.0 grams of zinc 2) 19.5 grams of Al(OH)3 3) 2.00 moles of nitrogen gas 4) 1.60 x 10^-2 moles of...

Convert masses into moles for 1 and 2, convert moles into masses for 3 and 4.

Show all work

1) 40.0 grams of zinc

2) 19.5 grams of Al(OH)3

3) 2.00 moles of nitrogen gas

4) 1.60 x 10^-2 moles of H2SO4

How many atoms of chlorine are in 19.0 grams of MgCl2?

What is the volume of 2.60 moles of CO2(g) at STP?

What is the mass of 20.00 liters of N2(g) if the temperature is 0 degrees Celsius and the pressure is 101.3 kPa?

How many grams of Na(s) are needed to react completely with 710. grams of Cl2(g)?

WHat volume of oxygen gas must react (at stp) in order to produce 100. grams of NaClO3?

jeew-m | College Teacher | (Level 1) Educator Emeritus

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Molar masses

Zn = 65 g/mol

Al  = 27 g/mol

O  = 16g/mol

H  = 1 g/mol

N = 14 g/mol

S = 32 g/mol

1)

Mass of the Zinc sample         = 40g

Moles in the Zinc sample   = 40/65 mol

= 0.615 mol

2)

Mass of Al(OH)_3            = 19.5g

Molar mass of Al(OH)_3   = 2*27+3*16+3*1

= 105 g/mol

Moles of `Al(OH)_3`      = 19.5/105 mol

= 0.186 mol

3)

Moles of nitrogen gas     = 2

Mole mass of N_2 gas    = 2*14

= 28g/mol

Mass of `N_2` gas        = 2*28g

= 56g

4)

Moles of H_2SO_4 present    = 1.6xx10^-2

Molar mass of `H_2SO_4`       = 2*1+1*32+4*16

= 98 g/mol

Mass of `H_2SO_4`              = 1.6xx10^-2*98

= 1.568g