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1. How many molecules of hydrogen is produced if one drops a 5g piece of sodium into 250ml of water?

The balanced equation for it is:

2Na (s) + 2H2O (l) ---> 2NaOH (s) + H2 (g)

2. If you used 45ml of hydrogen peroxide that has a density of 1.003 g/cm^3, how many grams of each product would be produced?

The balanced equation for it is:

2H2O2 (l) ---> 2H2O (l) + O2 (g)

Note: There's a KI catalyst on the equation above (supposed to be above the arrow)

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Anyways, these are the last two questions on my little project thing that's due tomorrow and I suck at chemistry.

Can anyone help me out?

1.) idk if this is right or not (ie.. the calculations).. convert everything to mols, because when we look at a chemical equation, one way to look at it is that what we're seeing is the relative mole ratios of the reaction taking place so now.. to the conversion

(5g Na)/(22.98977)=0.217488 mol Na (the 22.98977 is the AMU of Na)

0.217488/2 =0.108744mol H2

0.107844(6.022e+23)=6.49436568e+22 molecules

2.) V=45mL H2O2 rho=1.003g/cm^3

1mL=1cm^3

1.003=mass/45 mass = 45.135 H2O2

45.135/(34)=1.3275 mol H2O2 (34=MMU of H2O2)

the relative mol ratio is the same so i used the same number of mols as i found for H2O2 and just converted it into mass 1.3275(18)=23.895g H2O

here the mol ratio of O2 is half that of the H2O2 so i halved it and converted to grams (1.3275/2)(32)=21.24g O2