Answer:
Option a. 4 g of He
Explanation:
6.02×10²³ is the Avogadro's number. The amount of units that corresponds to 1 mol, in this case the units are molecules.
Let's find out which mass corresponds to 1 mol (mass / molar mass)
a. 4g / 4g/mol = 1 mol He
b. 14g / 6.94 g/mol = 2.01 mol Li
c. 80g /159.8 g/mol = 0.5 moles Br₂
d. 4g / 2g/mol = 2 mol H₂
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:
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.
= 0.448 L
They want answer in mL. So, let's convert L to mL using the conversion formula, 1L = 1000mL
= 448 mL
So, 0.020 moles of magnesium would produce 448 mL of hydrogen gas at STP on reacting with excess of HCl acid.
Answer:
Explanation: A renewable resource is a natural resource which will replenish to replace the portion depleted by usage and consumption, either through natural reproduction or other recurring processes in a finite amount of time in a human time scale.