There are several differences between<span> a </span>physical and chemical change<span> in matter or substances. A </span>physical change<span> in a substance doesn't </span>change<span> what the substance is. In a </span>chemical change<span> where there is a </span>chemical<span> reaction, a new substance is formed and energy is either given off or absorbed.</span>
Answer: 2948
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
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 = 
Thus the fossil is 2948 years old.
Answer:
san franciso is 3 hours beind and with NewYork
Explanation:
Answer:
<h3>The precipitate is MgCl2</h3>
Explanation:
The reaction that is described goes as follows:
2AgCl + Mg(OH)2 ---> MgCl2 + 2AgOH
The precipitate here is the MgCl2 salt.
I hope it helped!
Explanation:
Mole ratio of Oxygen to Hydrogen gas = 1 : 2.
If we use 3.0 moles of oxygen gas, we would need 3.0 * 2 = 6.0 mol of hydrogen gas.
However we only have 4.2 mol of hydrogen. Therefore hydrogen is limiting and oxygen is in excess. (B)
