Given:
P1 = 50 kPa
V1 = 5.0 L
P2 = 125 kPa
V2 = ?
Boyle's Law
P1V1 = P2V2
50 * 5 = 125 * V2
250 = 125 * V2
250 / 125 = V2
2 = V2
Answer is letter C. 2.0 L
Mass number is sum of protons and neutrons so 22+26
The sum would be 48
Mass number is 48
"the same";
One mole of any given thing is 6 * 10²³ of it;
One mole of H₂O is 6 * 10²³ molecules;
One mole of O₂ is also 6 * 10²³ molecules;
Therefore for both substances, there are the same number of molecules.
Missing question: Z:X = 7:1 A:Z = 2.5:1 A:Z = 2.2:1 Y:X = 11:1.
Answer is:<span> Z:X = 7:1 and Y:X = 11:1.
Law of multiple proportions or Dalton's Law
said that the ratios of the masses of the second element which
combine with a fixed mass of the first element will be ratios of small whole
numbers.
In this example ratios are whole numbers, A:Z = 2.5 : 1
and A:Z = 2.2 : 1 are not whole number ratios.</span>