Answer:
6.25 grams is the mass of solute dissolved.
Explanation:
w/w % : The percentage mass or fraction of mass of the of solute present in total mass of the solution.
Mass of the solution = 50.0 g
Mass of the solvent = x
w/w % = 12.5%
x = 6.25 g
6.25 grams is the mass of solute dissolved.
.90 dL is 90 mL because 1 dL is 100 mL
Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
Answer: 373 mL
Explanation:
Since there is no change in pressure, the formula: V / T = V / T can be used.
However, you must first convert the temperatures to Kelvin by adding 273 to them:
(19 + 273) = 292K and (90 + 273) = 363K.
Now, plug in: V / 292 = 464 / 363 → V = 373 mL :)
