Answer:
Explanation:
We are asked to find the pressure of a gas given a change in volume. Since the temperature remains constant, we are only concerned with volume and pressure. We will use Boyle's Law, which states the volume is inversely proportional to the pressure. The formula for this law is:
Initially, the oxygen gas occupies a volume of 18.7 liters at a pressure of 1.19 atmospheres.
The gas expands to a volume of 29.4 liters, but the pressure is unknown.
We are solving for the new pressure, so we must isolate the variable . It is being multiplied by 29.4 liters. The inverse operation of multiplication is division. Divide both sides of the equation by 29.4 L.
The units of liters cancel.
The original measurements all have 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place. The 9 in the ten-thousandth place to the right of this place tells us to round the 6 up to a 7.
The pressure of the gas sample is approximately <u>0.757 atmospheres.</u>
Answer:
A chemical change occurred and a gas was produced.
Step-by-step explanation:
If there is no chemical reaction, the <em>Law of Conservation of Mass</em> says that
Total mass = Mass 1 + Mass 2
However, if the two liquids react and give off a gas, then
Total mass = Mass 1 + Mass 2 + Mass of gas
You are not measuring the mass of the gas, so the mass of the liquids after mixing is less than it was before mixing.
For example, if Liquid 1 was a solution of HCl and Liquid 2 was a solution of Na₂CO₃, they would give off CO₂ on mixing. but you would not be measuring the mass of the CO₂.