<u>Answer:</u> The amount of calcium hydroxide needed to react is 2.04 moles
<u>Explanation:</u>
We are given:
Moles of phosphoric acid = 1.36 moles
For the given chemical equation:
By Stoichiometry of the reaction:
2 moles of phosphoric acid reacts with 3 moles of calcium hydroxide
So, 1.36 moles of phosphoric acid will react with = 
of calcium hydroxide
Hence, the amount of calcium hydroxide needed to react is 2.04 moles
Answer:
THE NEW PRESSURE OF THE HELIUM GAS IS 124kPa AFTER THE VOLUME WAS INCREASED FROM 2.48 L TO 2.98 L
Explanation:
Using Boyle's law which states that at constant temperature, the pressure of a given gas is inversely proportional to the volume occupied by the gas.
Mathematically,
P1 V1 = P2 V2
P1 = 150 kPa = 150 * 10^3 Pa
V1 = 2.48 L
V2 = 2.98 L
P2 = ?
Rearranging the formula making P2 the subject of the equation, we obtain;
P2 = P1 V1 / V2
P2 = 150 * 10^3 * 2.48 / 2.98
P2 = 372 * 10 ^3 / 2.98
P2 = 124.83 * 10^3 Pa or 124.8kPa
In other words, the new pressure of the helium gas after its volume was increased from 2.48 L to 2.98 L is 124.8kPa.
Answer:
D. it's a displacement reaction
