Answer:
there are 3 significant figures
Explanation:
do not count the first 2 zeros. only the nimbers after the zero
HCI is the limiting reactant, and 4.3 mol AICI3 can be formed.
Answer:
Molarity is 0.99 M
Explanation:
5.21% by mass, is a sort of concentration which shows the mass of solute in 100 g of solution.
Molarity is a sort of concentration that indicates the moles of solute in 1 L of solution (mol/L)
Let's find out the volume of solution by density.
Solution density = Solution mass / Solution volume
1.15 g/mL = 100 g / Solution volume
Solution volume = 100 g / 1.15 g/mL → 86.9 mL
We must have the volume of solution in L, so let's convert it.
86.9 mL / 1000 = 0.0869 L
Now, we have to determine the moles of solute (urea)
5.21 g . 1 mol / 60 g = 0.0868 moles
Mol/L = Molarity → 0.0868 moles / 0.0869L = 0.99 M
Physical change
iron nail have high melting point, thus, when it is heated, it will not melt very easily.
chemical change
iron nail can rust due to the exposure to the air(oxygen). iron in the nail and oxygen in the air will react together to form iron oxide(rust).
furthermore, the reaction is irreversible.
Because of the heat, steam