Answer: 4.22 grams of solute is there in 278 ml of 0.038 M 
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
where,
n = moles of solute
= volume of solution in L
Now put all the given values in the formula of molality, we get
mass of = 
Thus 4.22 grams of solute is there in 278 ml of 0.038 M
Answer: I believe the correct answer would be A.
Answer:
The mass of an atom is found in its nucleus.
Explanation:
An atom is made of three different particles: protons, neutrons and electrons.
Protons (positive charge) and neutrons (no charge) each have a mass of 1 AMU. They are both found in the nucleus (centre) of the atom.
Electrons (negative charge) are considered to have a mass of 0. Their mass is not actually 0, but very close so we do not count them. They are not in the nucleus, but found in shells surrounding the atom.
To calculate the mass of an atom, we add the number of protons and the number of electrons.
m = P + N
Answer:
Explanation:
Mass of compound A = 25g
Mass of compound B = 40g
Mass of final mixture = 55g
What happens to the missing mass?
According to the law of conservation of mass, in chemical reaction, matter is transformed from one form to another but cannot be created nor destroyed.
We expect the final mass of the mixture and that of the reacting compounds to be the same but the opposite is the case.
There is a mass loss which typifies most chemical reaction.
The reason for this is that some of the masses must have been lost by the production of gaseous species which are unaccounted for.
The missing mass:
Total mass expected = mass of A + mass of B = 25 + 40 = 65g
Missing mass = expected mass - mass of final mixture = 65 - 55 = 10g
