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# Chemistry Help!! Watch

1. Write the balanced equation when calcium (10g) reacts with excess Hyrdrochloric acid to give a salt and hydrogen gas.
a) Find the mass of hydrogen produced
b) Find the volume of H2 produced.
AR= H-1, Cl- 35.5, Ca-14 Molar Volume=24000cm

Please can someone show me how to do this (step by step)
2. First 2Ca + 2hcl = 2Cacl + h2
Get moles of Ca moles = mass / ar = 10/14 = 0.71
So now we assume Hcl has same moles 0.71 then convert cm3 volume to dm3 by 24000/1000 24dm3
So mass of h2 =moles x ar = 0.71 *1 = 0.71
Then v =molesx24 = 0.71*24 = 17.04g
3. Isn't the ar of ca 40 ????
4. (Original post by Fermion12)
First 2Ca + 2hcl = 2Cacl + h2
Get moles of Ca moles = mass / ar = 10/14 = 0.71
So now we assume Hcl has same moles 0.71 then convert cm3 volume to dm3 by 24000/1000 24dm3
So mass of h2 =moles x ar = 0.71 *1 = 0.71
Then v =molesx24 = 0.71*24 = 17.04g
I understand it, thank you! But why are you converting cm3 to dm3?
5. (Original post by Fermion12)
Isn't the ar of ca 40 ????
That's why I though but my teacher put 14 so...
6. I was taught to convert because the actual volume used to do calculations is dm3 only in practical work is cm3 used i guess
7. By the way do you have a source for the actual answers of this question please i request you notify me if the answers i got were correct or not if not then my apologies if yes Your welcome !🙆
8. I think the answers will be incorrect as the ar used is wrong in my opinion i referred to the periodic table there it has been stated as 40 so im really confused 😐😐
9. (Original post by thea_)
Write the balanced equation when calcium (10g) reacts with excess Hyrdrochloric acid to give a salt and hydrogen gas.
a) Find the mass of hydrogen produced
b) Find the volume of H2 produced.
AR= H-1, Cl- 35.5, Ca-14 Molar Volume=24000cm

Please can someone show me how to do this (step by step)
I'm more interested on how the respondents to this thread have not picked out that the relative atomic of mass of Ca isn't 14! It's around 40
10. (Original post by Fermion12)
By the way do you have a source for the actual answers of this question please i request you notify me if the answers i got were correct or not if not then my apologies if yes Your welcome !🙆
Sure, i will when I get the answers
I'm more interested on how the respondents to this thread have not picked out that the relative atomic of mass of Ca isn't 14! It's around 40
i did my friend but as a matter of fact i just posted above 👍 but i just wanted to provide a fundamental procedure on how to do it
12. (Original post by Fermion12)
First 2Ca + 2hcl = 2Cacl + h2
Get moles of Ca moles = mass / ar = 10/14 = 0.71
So now we assume Hcl has same moles 0.71 then convert cm3 volume to dm3 by 24000/1000 24dm3
So mass of h2 =moles x ar = 0.71 *1 = 0.71
Then v =molesx24 = 0.71*24 = 17.04g
Pretty sure volume isn't measured in grams...
Pretty sure volume isn't measured in grams...
I know cm3 obviously but i was typing on my extremely slow frustrating tablet therefore i mixed things up my bad .
14. (Original post by Fermion12)
I know cm3 obviously but i was typing on my extremely slow frustrating tablet therefore i mixed things up my bad .
I know, I'm just teasing
15. [QUOTE=GradeA*UnderA;67450780]I know, I'm just teasin lol 😂👍

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