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>
Answer:
<h2>7142.86 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>7142.86 moles</h3>
Hope this helps you
Answer:
Experimental: the dogs who get the toys
Control: the dogs who dont recieve a toy
Explanation:
expermental is the group that recieved the tested variable in this case that being the toy
control is the group that doesn't recieve the tested variable
Freezing point is defined as the temperature needed for a liquid to turn into a solid and a melting point is the temperature needed for a solid to become a liquid. Sodium Chloride has a lower freezing point than water, as such when it is added to icy roads it helps to melt the ice faster by lowering the melting point of the water making it turn into a liquid faster/easier even if it is "cold" outside.
