Answer:- 448 mL of hydrogen gas are formed.
Solution:- It asks to calculate the volume of hydrogen gas formed in milliliters at STP when 0.020 moles of magnesium reacts with excess HCl acid. The balanced equation is:
![Mg+2HCl\rightarrow MgCl_2+H_2(g)](https://tex.z-dn.net/?f=Mg%2B2HCl%5Crightarrow%20MgCl_2%2BH_2%28g%29)
There is 1:1 mol ratio between Mg and hydrogen gas. So, the moles of hydrogen gas is also equals to the moles of Mg reacted.
moles of Hydrogen gas formed = 0.020 mol
At STP, volume of 1 mol of the gas is 22.4 L. We need to calculate the volume of 0.02 moles of hydrogen gas.
![0.02mol(\frac{22.4L}{1mol})](https://tex.z-dn.net/?f=0.02mol%28%5Cfrac%7B22.4L%7D%7B1mol%7D%29)
= 0.448 L
They want answer in mL. So, let's convert L to mL using the conversion formula, 1L = 1000mL
![0.448L(\frac{1000mL}{1L})](https://tex.z-dn.net/?f=0.448L%28%5Cfrac%7B1000mL%7D%7B1L%7D%29)
= 448 mL
So, 0.020 moles of magnesium would produce 448 mL of hydrogen gas at STP on reacting with excess of HCl acid.
The correct answer is Gamma decay. It happens after beta and alpha decay
because what's left after those two can enter a new process of gamma
decay. This releases gamma rays which is a more complex term for the
photons that you mentioned before. These rays can be dangerous for
humans so care not to get caught in them.
Answer:
Here is one way: Add water to the mixture. Only the sugar dissolves. This is a physical change.
Explanation:
The sugar would dissolve in water. You could then pour off the solution and wash the remaining sand with a bit more water. Heat the water to evaporate it from the sugar, and the two are separated.
A. The heat is needed to melt 100.0 grams of ice that is already at 0°C is +33,400 J.
<h3>What is Specific heat capacity?</h3>
Specific heat capacity is the quantity of heat needed to raise the temperature per unit mass.
<h3>
Heat needed to melt the cube of ice</h3>
The heat is needed to melt 100.0 grams of ice that is already at 0°C is calculated as follows;
Q = mL
where;
- m is mass of the ice
- L is latent heat of fusion of ice = 334 J/g
Q = 100 x 334
Q = 33,400 J
Thus, the heat is needed to melt 100.0 grams of ice that is already at 0°C is +33,400 J.
Learn more about heat capacity here: brainly.com/question/16559442
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