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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Awgdawg on August 30, 2015, 05:45:05 PM

Title: Basic Help with Chemistry
Post by: Awgdawg on August 30, 2015, 05:45:05 PM
I'm having trouble trying to find quick answers for these questions:

1: 10g sample of an oxide is heated in a stream of pure hydrogen forming 1.26g of water.
a)Determine the percentage copper in the compound
b)Determine the empirical formula of the copper oxide. Name it.

2: Nonprescription antacids may contain MgO, Mg(OH)2, or Al(OH)3.
a) Write a chemical equation for the neutralization of hydrochloric acid by each of these substances.
b) Which of these substances will neutralize the greatest amount of .1 M HCL per gram?

Title: Re: Basic Help with Chemistry
Post by: Arkcon on August 30, 2015, 08:51:38 PM
I'd like to welcome you, Awgdawg:, the the Chemical Forums, but I'd like to ask you to read the Forum Rules{click} (http://www.chemicalforums.com/index.php?topic=65859.0).  We like to help you learn to help yourself.  Can yu begin to show us your attempt?
Title: Re: Basic Help with Chemistry
Post by: Awgdawg on August 30, 2015, 11:49:16 PM
So after waiting a while, I was able to come up with an answer to #1 but #2 is still questionable.

For part a I was able to come up with with the 3 equations:

2HCl + MgO  :rarrow:  MgCl2 + water

Mg(OH)2 + 2HCl  :rarrow:  MgCl2 + 2water

Al(OH)3 + 3HCl  :rarrow:  AlCl3 + 3water

After this part, I have trouble finding the greatest amount of .1 M HCl per gram. I first look at the ratios between the acid and the antacid. I find the ratios (1:2) (1:2) (1:3). From this result I'm looking at the Aluminum hydroxide as the answer. I read further into the question and says," ... greatest amount of .1 M HCl per gram." At this point I don't know what equation to use. I'm not sure if the .1 M HCl is redundant or not, or if I put the moles of HCl over each equations' respective masses of the antacids to find an answer.
Title: Re: Basic Help with Chemistry
Post by: Borek on August 31, 2015, 03:00:05 AM
Quote from: Awgdawg on August 30, 2015, 11:49:16 PM
After this part, I have trouble finding the greatest amount of .1 M HCl per gram

How much HCl can be neutralized by 1 gram of MgO?

How much HCl can be neutralized by 1 gram of Mg(OH)2?

Which can neutralize more HCl per 1g?

What about Al(OH)3?

Quote
10g sample of an oxide is heated in a stream of pure hydrogen forming 1.26g of water.

How many moles of oxygen reacted? What is mass of this oxygen?