<h3><u>Answer;</u></h3>
= 11,460 years
<h3><u>Explanation;</u></h3>
- <em><u>The half life of Carbon-14 is 5,730 years
. Half life is the time taken by a radioactive material to decay by half of its original mass. Therefore, it would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams</u></em>
<em>The initial amount of carbon-14 in this case was 1 whole; thus; </em>
<em>1 → 1/2 →1/4</em>
<em>To contain 1/4 of the value, 2 half-lives have passed.
</em>
<em>But, 1 half life = 5,730 years</em>
<em>Therefore; The artifact is is therefore: 2 x 5,730
</em>
<em> = 11,460 years </em>
Answer:
56972.17K
Explanation:
P = 4.06kPa = 4.06×10³Pa
V = 14L
n = 0.12 moles
R = 8.314J/Mol.K
T = ?
We need ideal gas equation to solve this question
From ideal gas equation,
PV = nRT
P = pressure of the ideal gas
V = volume the gas occupies
n = number of moles
R = ideal gas constant
T = temperature of the gas
PV = nRT
T = PV / nR
T = (4.06×10³ × 14) / (0.12 × 8.314)
T = 56840 / 0.99768
T = 56972.17K
Note : we have a large number for temperature because we converted the value of pressure from kPa to Pa
Answer:
is the limiting reagent
Explanation:
To calculate the moles :


The balanced chemical reaction is :
According to stoichiometry :
1 moles of
require = 2 moles of 
Thus 0.625 moles of
will require=
of 
Thus
is the limiting reagent as it limits the formation of product and
is the excess reagent as it is present more than the required amount.
The melting of solid wax to form liquid wax and the evaporation of liquid wax to form wax vapor are physical changes. The burning of the wax vapor is a chemical change.
Answer:
70.77 g/mol is the molar mass of the unknown gas.
Explanation:
Effusion is defined as rate of change of volume with respect to time.
Rate of Effusion=
Effusion rate of oxygen gas after time t = 
Molar mass of oxygen gas = M = 32 g/mol
Effusion rate of unknown gas after time t = 
Molar mass of unknown gas = M'
The rate of diffusion of gas, we use Graham's Law.
This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:



M' = 70.77 g/mol
70.77 g/mol is the molar mass of the unknown gas.