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nserant
May 29, 2009, 08:52 PM
Magnesium nitride reacts with water to produce magnesium hydroxide according to the following balanced equation: Mg2N2+6H2O=3Mg(OH)2 + 2NH3, How many grams of magnesium hydroxide can be produced from 200 grams of magnesium nitride

kp2171
May 29, 2009, 09:11 PM
Well... you need to do some work.

Convert grams of mag nitride to moles of mag nitride using the molecular weight. If you cannot do this, you need to learn to do this... look at your book and your class notes.

Once you get moles of mag nitride you need to convert moles of mag nitride to moles of mag hydroxide... notice how the balanced eq shows 1 mg2n2 for every 3mg(oh)2?. that would mean one mole of mag nitride would produce three moles of the mag hydroxide...

Then you convert moles to grams using the molecular formula...

We will NOT do your homework for you... but you can try the work and post your answers or the places you are stuck and we will work with you...

Unknown008
May 30, 2009, 05:40 AM
Follow KP explanations and you'll be fine. All was said.

Just to resume visually;

Mg_3N_2+6H_2O=3Mg(OH_)2 + 2NH_3

1 mole of Mg_3N_2 has a mass of 100g

x moles of Mg_3N_2 has a mass of 200g

1 mole of Mg_3N_2 gives 3 moles of Mg(OH)_2

x moles of Mg_3N_2 gives 3x moles of Mg(OH)_2

1 mole of Mg(OH)_2 has a mass of 58g

3x moles of Mg(OH)_2 has a mass of ?g

nserant
May 30, 2009, 06:27 PM
0.35 moles of ammonium sulfate would have a mass of what grams

nserant
May 30, 2009, 06:28 PM
The molar mass of bromine gas is

Perito
May 30, 2009, 07:45 PM
Heavens man. At least TRY. As a minimum, look up the molecular weight of the compounds. All you have to do is multiply or divide by the molecular weight to convert from moles to grams or vice-versa.

kp2171
May 30, 2009, 07:55 PM
Please read site rules.

We will not do homework for you... and you haven't yet posted a single attempt at an answer...

Unknown008
May 31, 2009, 07:40 AM
0.35 moles of ammonium sulfate would have a mass of what grams

the molar mass of bromine gas is

Gosh! You asked for a certain level of question, and now, you kind of suddenly dropped down! Seems that you don't have a strong foundation in your chemistry...

I'll try my best to explain to you;

1 mole of any atom has a mass equal to its relative atomic mass, which you have in every periodic table.

Now, 1 mole of a substance has a mass equal to the sum of the relative masses contained in that substance.

For example, hydrogen has a relative atomic mass of approximately 1, so, one mole of hydrogen atoms will have a mass of 1 g.

However, hydrogen atoms do not exist in nature. They are in the form of hydrogen molecules, H_2

So, the mass of 1 mole of hydrogen gas will be (mass of 2 hydrogen atoms) 2g

Now, a compound, say salt, with formula NaCl. Mass of 1 mole of Na atoms is 23g and mass of 1 mole of Cl atoms is 35.5g.

Mass of 1 mole NaCl therefore is 58.5g (from 23 + 35.5)

Mass of 1 mole of rust (Fe_2O_3) is 160 g ( 2(56) + 3(16))

Understood?