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
The Equator is where the doldrums are found.
Copper oxide is the only product, and it contains copper and oxygen.
one of the reactants is copper, so the other reactant must be oxygen.
The copper metal must have combined with something in the air.
Answer:
Argon gas
Explanation:
Between the options given, argon gas is the least reactive. Argon is known as a <em>noble gas</em>, this means that it is located in the group 18 in the periodic table. These gases are known for their low reactivity, under most circumstances.
The <u>electronic configuration</u> of argon helps us see why that is the case: With an atomic number of 18, it has an electronic configuration of 1s² 2s² 2p⁶ 3s² 3p⁶. This means the most external orbital is filled with electrons, meaning that there are not unpaired electrons able to react with other substances.
Mass = 90.0 g
Density = 0.70 g/mL
Volume = in mL ?
D = m / V
0.70 = 90.0 / V
V = 90.0 / 0.70
V = 128.57 mL
