Answer:
C6H6
Explanation:
We can obtain the molecular formula from the empirical formula.
What we need do here is:
(CH)n = 78
The n shows the multiples of both element present in the actual compound. It can be seen that carbon and hydrogen have the same element ratio here. We then use the atomic masses of both elements to get the value of n. The atomic mass of carbon is 12 a.m.u while the atomic mass of hydrogen is 1 a.m.u
(1 + 12)n = 78
13n = 78
n = 78/13 = 6
The molecular formula is
(CH)n = (CH)6 = C6H6
Answer:
mass number = 18
Explanation:
The mass number is the total amount of protons and neutrons in an atom. Therefore, if there are 8 protons and 10 neutrons, the mass number is 18 (8 + 10 = 18).
1) Use the fact that 1 mol of gas at STP occupies 22.4 liter
=> 1 mol / 22.4 l = x / 0.125 l => x = 0.125 l * 1 mol / 22.4 l = 0.00558 mol
2) Now use the molar mass of the gas
molar mass of CO2 ≈ 44 g / mol
Formula: molar mass = mass in grams / number of moles =>
mass in grams = molar mass * number of moles = 44 g/mol * 0.00558 moles
mass = 0.246 g
Answer: 0.246 g
Answer:
0.805 M.
Explanation:
Hello!
In this case, since the molarity of a solution is computing by dividing the moles of solute over the volume of solution in liters (M=n/V), for 15.0 g of potassium chloride (74.55 g/mol) we compute the corresponding moles:
Next, since the volume is 0.2500 in liters, the molarity turns out:
Best regards!
No, because 40 miles is the same as nearly 25 km/h.
