I need so much help with my chemistry homework because I have been stuck for days please help me as soon as possible please

Question

1.) 3 Cu + 8HNO3 --> 3 Cu(NO3)2   + 2 NO + 4 H2O

In the above equation how many moles of water can be made when 25 moles of HNO3 are consumed?

2.) Sodium chlorate decomposes into sodium chloride and oxygen gas as seen in the equation below. 

­­2NaClO3­ --> 2NaCl +3O2

How many moles of NaClO3­ were needed to produce 44 moles of O2? Round your answer to the nearest whole number.

please help me by explaining and solving please

Answer 1

Hi Lulu S.

Make sure you have balanced equations. Just use the moles from the balanced equations as ratio to solve for the unknown amounts.

2.) Sodium chlorate decomposes into sodium chloride and oxygen gas as seen in the equation below. 

2NaClO3­ --> 2NaCl +3O2

This says when 2 moles of Sodium chlorate decomposes, you get 3 moles of Oxygen gas,

2 moles of Sodium chlorate/3 moles of Oxygen gas

2 moles of Sodium chlorate/3 moles of Oxygen gas = x moles of Sodium chlorate/44 moles of Oxygen gas

Just cross multiply to solve for x

The same process applies in question 1.