Answer:
Balancing chemical equation means making a number of atoms or molecules equal on both sides. In other words, this means that the number of atoms and molecules of each reacting element needs to be the same as the number of atoms and molecules of those elements in the product.
Our reaction is:
AlBr3 + K2SO4 -> KBr + Al2(SO4)3
and we need to balance it.
Since there are 3 molecules of SO4 in the product we need to put 3 before the reactant K2SO4. There are also 2 atoms of Al in the product, so we need to put 2 in front AlBr3. Now we have 6 atoms of K and Br on the left side, so we need to put 6 in front of KBr in the product.
So, our balanced equation will look like this:
2AlBr3 + 3K2SO4 -> 6KBr + Al2(SO4)3
Answer:
The rates of decay of radioactive elements
Explanation:
The age of a rock in years is called its absolute age. Geologists find absolute ages by measuring the amount of certain radioactive elements in the rock. When rocks are formed, small amounts of radioactive elements usually get included.
Radioactive material undergoes 1st order decay kinetics.
For 1st order decay, half life = 0.693/k
where k = rate constant
k = 0.693/half life = 0.693/8.02 = 0.0864 day-1
Now, for 1st order reaction,
k =
Given: t = 6.01d, initial conc. = 5mg
∴0.0864 =
∴ final conc. = 2.975 mg
Explanation:
sodium atom is neutral while sodium ion is a charged specie with a charge of +1
Hope you understand how to work out those types of questions now xD ;)
