Mass number is the sum of protons and neutrons inside an atom.
Atomic mass = no. of protons + no. of neutrons
Answer: must have THE SAME number of atoms for each element
Explanation: Chemical equations must be balanced -- they must have the same number of atoms of each element on both sides of the equation. As a result, the mass of the reactants must be equal to the mass of the products of the reaction.
Answer:
The pressure of the gas will "increases by a factor of four."
Explanation:
The absolute zero in other words called as the absolute temperature. Whereas the absolute zero is the least possible temperature. In which nothing will remain cold and no heat can be released or present in the substance. When it is described in the figure it will be, –273.15 degrees Celsius on the Celsius scale. and 0 K on the Kelvin scale. This absolute temperature concept has been raised from the third law of the thermodynamics.
Answer: -
3.151 M
Explanation: -
Let the volume of the solution be 1000 mL.
At 25.0 °C, Density = 1.260 g/ mL
Mass of the solution = Density x volume
= 1.260 g / mL x 1000 mL
= 1260 g
At 25.0 °C, the molarity = 3.179 M
Number of moles present per 1000 mL = 3.179 mol
Strength of the solution in g / mol
= 1260 g / 3.179 mol = 396.35 g / mol (at 25.0 °C)
Now at 50.0 °C
The density is 1.249 g/ mL
Mass of the solution = density x volume = 1.249 g / mL x 1000 mL
= 1249 g.
Number of moles present in 1249 g = Mass of the solution / Strength in g /mol
= 
= 3.151 moles.
So 3.151 moles is present in 1000 mL at 50.0 °C
Molarity at 50.0 °C = 3.151 M
