Are my answers correct> please show work. The formula for the illegal drug cocai

Question

Are my answers correct> please show work.

The formula for the illegal drug cocaine is C17H21NO4. What is the mass percentage of oxygen in the compound? (Answer: 22.12%)

What is the mass of silver metal produced from 6.35 g of copper? Answer: 21.6g

Cu(s) + 2AgNO3(aq)   Cu(NO3)2(aq) + 2Ag(s)

What is the mass of copper metal that yields 0.500 g of silver? 0.147g Cu

             Cu(s) + 2AgNO3(aq)   Cu(NO3)2(aq) + 2Ag(s)

What is the volume of oxygen gas at STP from the decomposition of 1.70 g of NaNO3 (MM = 85.00 g/mol)? Answer: 0.0224L

2NaNO3 (s) ---(spark) 2NaNO2 (s) + O2(g)

Explanation / Answer

1)

Molar mass of C17H21NO4,

MM = 17*MM(C) + 21*MM(H) + 1*MM(N) + 4*MM(O)

= 17*12.01 + 21*1.008 + 1*14.01 + 4*16.0

= 303.35 g/mol

MM of C17H21NO4 = 303.35

Lets calculate the mass of element

mass of O = 4*MM(O) = 64.00 g

Mass % of O = (64.00*100)/303.35 = 21.1 %

Answer: 21.1 %

This is correct

2)

mol of Cu = mass of Cu / molar mass of Cu

= 6.35 / 63.5

= 0.1 mol

from reaction,

mol of Ag = 2*mol of Cu

= 2*0.1 mol

= 0.2 mol

mass of Ag = mol of Ag * molar mass of Ag

= 0.2 mol * 108 g/mol

=21.6 g

This is correct

3)

mol of Ag = mass of Ag / molar mass of Ag

= 0.500 / 108

= 0.00463 mol

from reaction,

mol of Cu reacted = mol of Ag / 2

= 0.00463 mol / 2

= 0.002315 mol

mass of Cu = mol of Cu * molar mass of Cu

= 0.002315 mol * 63.5 g/mol

=0.147 g

this is correct

I am allowed to answer only 1 question at a time

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.