Answer: The age of the tool is 15539 years
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = 100
a - x = amount left after decay process =
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.

b) for 15.5 % of original amount

Thus age of the tool is 15539 years
As Fire needs oxygen to burn, Carbon Dioxide Covers the fire like an blanket and cuts the contact of fire to the oxygen present in the air, So Fire stops burning.That is why Carbon Dioxide is Considere as the best Fire Extinguisher.
We first need to find the number of moles of gas in the container
PV = nRT
where;
P - pressure - 2.87 atm x 101 325 Pa/atm = 290 802.75 Pa
V - volume - 5.29 x 10⁻³ m³
n - number of moles
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 230 K
substituting these values in the equation
290 802.75 Pa x 5.29 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 230 K
n = 0.804 mol
the molar mass = mass present / number of moles
molar mass of gas = 56.75 g / 0.804 mol
therefore molar mass is 70.6 g/mol
0.52164 kg of Flour
<u>Explanation:</u>
We have to convert lb (pounds) kg (kilograms), by using the conversion unit,
1 lb = 0.4536 kg
So to convert 1.15 lb into kg, we have to multiply 1.15 by 0.4536.
= 0.52164 kg of Flour
So the receipt calls for 0.52164 kg of Flour.
Answer:
i. Molar mass of glucose = 180 g/mol
ii. Amount of glucose = 0.5 mole
Explanation:
<em>The volume of the glucose solution to be prepared</em> = 500 
<em>Molarity of the glucose solution to be prepared</em> = 1 M
i. Molar mass of glucose (
) = (6 × 12) + (12 × 1) + (6 × 16) = 180 g/mol
ii.<em> mole = molarity x volume</em>. Hence;
amount (in moles) of the glucose solution to be prepared
= 1 x 500/1000 = 0.5 mole