How many moles of water are produced when 10 moles of hydrogen gas reacts with an excess of oxygen? (whole number)

12 moles H

2

O

Explanation:

Your tools of choice for stoichiometry problems will always be the mole ratios that exist between the chemical species that take part in the reaction.

As you know, the stoichiometric coefficients attributed to each compound in the balanced chemical equation can be thought of as moles of reactants needed or moles of products formed in the reaction.

In your case, the balanced chemical equation for this synthesis reaction looks like this

2

H

2(g]

+

O

2(g]

→

2

H

2

O

(l]]

Notice that the reaction requires  

2

moles of hydrogen gas and  

1

mole of oxygen gas to produce  

2

moles of water.

This tells you that the reaction produces twice as many moles of water as you have moles of oxygen gas that take part in the reaction.

You know that your reaction uses  

6.0

moles of oxygen. Assuming that hydrogen gas is not a limiting reagent, you can say that the reaction will produce

6.0

moles O

2

⋅

2

moles H

2

O

1

moles O

2

=

12 moles H

2

O

Explanation:

3

explanation:

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6