Question

Use the following equation to answer the questions and please show all work.

Answer 1

a.36 g of water is produced.

b.64 g of
`O_(2)` is consumed.

Step-by-step explanation:

The reaction is
`2H_(2) + O_(2)`⇒
`2H_(2)O`

a.

Given,

Weight of
`H_(2)` reacted = 4g

Weight of 1 mole of
`H_(2)` = 2
`*`1 = 2g

Therefore no. of moles of
`H_(2)` reacted =
`(4)/(2)` = 2 moles;

Also given,

Weight of
`O_(2)` reacted = 32 g

Weight of 1 mole of
`O_(2)` = 2
`*`16 = 32 g

Therefore no. of moles of
`O_(2)` reacted =
`(32)/(32)` = 1

We know that 2 moles of Hydrogen reacts with 1 mole of Oxygen to give 2 moles of water,

As we took 2 moles of Hydrogen and 1 mole of Oxygen,

Directly,from the equation we can tell 2moles of water will be produced.

Therefore no. of moles of
`H_(2) O` produced = 2

Weight of 1 mole of water =
`2* 1+16` = 18

Therefore weight of
`H_(2)O` produced =
`2* 18` = 36gm

b.

Given ,

72 g of
`H_(2)O` is produced.

So,

no. of moles of
`H_(2)O` produced =
`(72)/(18)` = 4 moles

From equation For every 2 moles of water formed , 1 mole of oxygen must be required.

So for producing 4 moles of water,

No. of moles of Oxygen required = 2 moles.

Therefore weight of
`O_(2)` reacted =
`2*32` = 64 g

Method 2:

Given,

8 g of
`H_(2)` has reacted.

So,

no. of moles of
`H_(2)` reacted =
`(8)/(2)` = 4 moles.

From equation , we know that For every 2 moles of
`H_(2)` reacted,1 mole of
`O_(2)` will react.

Therefore,

No. of moles of
`O_(2)` that reacts with 4 moles of
`H_(2)` =
`2*1` = 2 moles

Therefore the weight of
`O_(2)` reacted =
`2* 32` = 64 g