Answer:
Mass = 20 g
Explanation:
Given data:
Number of moles of He = 5 mol
Mass of He = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass = 4 g/mol
by putting values,
5 mol = Mass / 4 g/mol
Mass = 5 mol × 4 g/mol
Mass = 20 g
Answer:
A)
Explanation:
It estimates the probability of extinction.
In an unsaturated solution, the amount of solute is less than required in the solution. So, it can dissolve more solute.
Solid state is more dense than the liquid state as the molecules are closely packed in a solid.
Density is temperature dependent as with increase in temperature volume increases. So, the density decreases.
Like dissolves like. A polar solute will dissolve in a polar solvent.
So, the correct statement among the given options is B.For most substances, the solid state is more dense than the liquid state.
Your answer should be A and B
Always use least amount of sig figs possible. So this 9.7 would be (answer): 2 sig figs
