You would use the formula:
n =

Where m is the mass, and M is molar mass (the periodic table would be used for this)
In this case, we need to rearrange the formula to find m
m = nM
= 5.40 x 6.941
= 37.5g
Hope this helped! Ask me if there's any part of the working you don't understand :)
Let the ratio of grams of hydrogen per gram of carbon in methane be M, we know that:
M = 0.3357 g / 1 g
Next, lets represent the grams of hydrogen per gram of carbon in ethane be E. The final piece of information we have is:
M / E = 4/3
If we cross multiply,
3M = 4E
Now, substituting the value of M from earlier and solving for E,
E = (3 * 0.3357) / 4
E = 0.2518
There are 0.2518 grams of hydrogen per gram of carbon in ethane.
B-10 = 19.9%
B-11 = 80.1%
Abundance of B10 = x
Abundance of B11= y
You know x+y = 1 because there are only the 2 isotopes.
Y= 1-x
10.01294x + 11.00931 (1-x) = 10.811
10.01294x + 11.00931 - 11.00931x = 10.811 - 0.99016x = -0.198
X = 0.200
Check:
10.01294(0.2) + 11.00931 (0.8) = 10.81
20% B10. 80% B11
Nope, its A i just took the test
<span>Two neutral hydrogen atoms share electrons in a covalent bond.
</span>
Answer:
may be...... false not sure
Explanation: