(I) kinetic energy of the boy when he hits the ground =potential energy
I. e ½mv²=mgh where g is 10ms-²
m=34kg, g=10ms² , h=3m
=34×10×3
=1020j
(i i) v²=u²+2gh
v²=0²+2×10×3
= 60
v=sqrt of 60
Calcium nitrate is limiting reactant, since it says there’s excess HCl. So you must use the mass of calcium nitrate in your calculation (see picture below):
Answer: yes
When the concentration of all the reactants increases then the rate of reaction increases. When the concentration decreases then the rate of reaction decreases.
This all because more molecules or ions form new compounds. Or losses.
3 Chlorine ions are required to bond with one aluminum ion.
In ionic bonds, metals atoms loses all its outermost shell electrons to form a cation. While, non metal atoms gains however many electrons in order to make its outermost electron shell be 8 (or 2 if there's only one shell).
Therefore, form the periodic table, we can see that aluminum has a atomic number of 13, which makes its electron arrangement be 2,8,3. So, in order to form a aluminum ion, an Al atom must lose 3 electrons. On the other hand, Chlorine has a atomic number of 17, which means it has the electron configuration of 2,8,7. It has to gain only 1 electron to have 8 outermost shell electron.
Thereofre, 3 Chlorine atom are required to gain all 3 electrons given out by just 1 aluminum ion.