The correct answer should be Letter B
Answer:
a. 0.119mol Kr
Explanation:
To solve this problem, we must understand that;
Mass = number of moles x molar mass
Molar mass of Kr = 83.3g/mol
Ar = 40g/mol
He = 4g/mol
Ne = 20.18g/mol
a0.119 mol Kr mass = 0.119 x 83.3 = 9.9g
b 0.400 mol Ar mass = 0.4 x 40 = 16g
C 1.25 mol He mass = 1.25 x 4 = 5g
d 2.02 mol Ne mass = 2.02 x 20.18 = 40.8
Krypton is the answer
The answers are
The age of the oldest stars
How fast distant galaxies are moving away from us
Patterns of background radiation.
Explanation:
The Astronomers calculate the age of the universe by looking for oldest stars, and by measuring the rate of expansion of the universe and back to big bang.
The Astronomers used the techniques like the age of oldest stars, how fast the distant galaxies are moving away from us, patterns of background radiation and along with the Big Bang as reference point, they estimate that the universe may be approximately 12 billion years old.
<span>the best answer is C i.e is ionoic compound. but all other option sare quite close enough but option B is sure wrong. because A molecular compound does not separate in a solvent.</span>
1mol—44g/mol
0.10mol—x
x=0.10*44
x=4.4 g