Here's how to do it:
<span>Balanced equation first: </span>
<span>Mg + HCl = H2 + MgCl2 unbalanced </span>
<span>Mg + 2 HCl = H2 = MgCl balanced </span>
<span>Therefore 1 mole Mg reacts with 2 moles Hcl. </span>
<span>50g Mg = ? moles (a bit over 2; you work it out) </span>
<span>75 g HCl = ? moles (also a bit over 2; you work it out) </span>
<span>BUT, you need twice the moles HCl; therefore it is the Mg that is in excess. (you can now work out how many moles are in excess, and therefore how much mg is left over). </span>
<span>So, 2 moles HCl produce 1 mole H2(g) </span>
<span>therefore, the amount of H2 produced is half the number of moles of HCl </span>
<span>At STP, there are X litres per mole of gas (look it up - about 22 from memory) </span>
<span>Therefore, knowing the moles of H2, you can calculate the volume</span>
If the hydrate gets too hot it could start splattering and cause a loss of sample.
Answer:
The number of hamburgers is 109.
Explanation:
Let h = number of hamburgers
Let c = number of cheeseburgers
The total number sold gives us the equation below.
h + c = 327
"The number of cheeseburgers sold was two times the number of hamburgers sold.
This gives us the equation
c = 2h
Now we substitute c with 2h in the first equation and solve for h.
h + 2h = 327
3h = 327
h = 109
The number of hamburgers is 109.
Answer:
C
Explanation:
that's really the only one that makes any sence
