Answer :
x = 53.85
Step by step explanation:
If 78% of x (some numbers) is equal to 42, then we must set this as an equation to find it.
1) Rewriting 78% as a fraction and considering that when we say 78% of some number (x) we mean a product.
78% = 78/100 ➡️ 78/100x = 42
2) Then we can go on :
100 * 78/100x = 42 * 100
78x = 4200
78x/78 = 4200/78 ➡️ x = 53.85
3) Alternatively, simply dividing 42 by 0.78 (78%) would come to the same result :
42/0.78 = 53.85
Answer:
Molar mass = 254.60g/mol
Step-by-step explanation:
Mass = 8.02g
Volume = 812mL = 0.812L
Pressure (P) = 0.967atm
Temperature of the gas = 30°C = (30 + 273.15)K = 303.15K
Molecular weight = ?
To solve this question, we'll have to use ideal gas equation, PV = nRT
P = pressure of the gas
V = volume of the gas
n = number of moles of the gas
R = ideal gas constant = 0.082J/mol.K
T = temperature of the gas
PV = nRT
n = PV / RT
n = (0.967 * 0.812) / (0.082 * 303.15)
n = 0.7852 / 24.8583
n = 0.0315 moles
Number of moles = mass / molarmass
Molarmass = mass / number of moles
Molar mass = 8.02 / 0.0315
Molar mass = 254.60g/mol
The molar mass of the gas is 254.60g/mol
Answer:
Hello,
I have reply too quick in comments (sorry)
Step-by-step explanation:

Answer: (b) A
<u>Step-by-step explanation:</u>
A: the center of the circle
B: the diameter of the circle
C: the radius of the circle
D: <em>not sure, could be the perimeter</em>
<em />
Circles are named by their center, so this is named "Circle A".