Answer:
THE MASS OF 7.68 *10^24 MOLECULES OF PHOSPHORUS TRICHLORIDE IS 1746.25 g.
Explanation:
Molar mass of PCl3 = ( 31 + 35.5 *3) = 137.5 g/mol
At 7.68 * 10^24 molecules, how many number of mole is present?
6.03 * 10^23 molecules = 1 mole
7.68*10^24 molecules = x mole
x mole = 7.68 *10^24 molecules/ 6.03 *10^23
x mole = 1.27 *10 moles
x mole = 12.7 moles
Using mole = mass / molar mass
mass = mole * molar mass
mass = 12.7 moles * 137.5 g/mol
mass = 1746.25 g
Hence, the mass of 7.68 *10^24 molecules is 1746.25 g
The chemical formula for ammonia is NH3. So first, you need to find the molar mass of ammonia (how many grams in one mole).
N=14g
H3=3g
So one mole of NH3 is 17 grams, you can divide 82.9 grams by 17 grams to find the number of molecules. The answer should be 4.876 moles (molecules) of ammonia. Hope this helps!
Explanation:
The mode is the most common number.
Um = 55
The mean is the sum of the numbers divided by the quantity.
Uavg = (38 + 44 + 45 + 48 + 50 + 55 + 55 + 57 + 58 + 60) / 10
Uavg = 51
The RMS (root mean square) is the square root of the sum of the squares of the numbers divided by the quantity.
Urms = √[(38² + 44² + 45² + 48² + 50² + 55² + 55² + 57² + 58² + 60²) / 10]
Urms = 51.451
Answer:
GP.E = 5880 j
Explanation:
Given data:
Mass = 75 kg
height = 8 m
Potential energy = ?
Solution:
The formula for gravitational potential energy is
GPE = mgh
m = mass in kilogram
g = acceleration due to gravity
h = height in meter above the ground
Formula:
GP.E = mgh
Now we will put the values in formula.
g = 9.8 m/s²
GP.E = 75 Kg × 9.8 m/s²× 8 m
GP.E = 5880 Kg.m²/s²
Kg.m²/s² = j
GP.E = 5880 j
<span>A 50-gram sample with a half-life of 12 days will have a remaining mass of 25 grams after its 12-day half-life.
Every cycle of a half-life, the sample will lose half of its mass, so if the half-life, itself, is 12 days and the time period passing is 12 days, one half-life has passed and the material will be halved.</span>
