1) list givens and convert if necessary
C₁ = 3.50 mol/L
V₁ = 0.550 L
C₂ = ?
V₂ = 0.275 L
2) rearrange formula
3) solve
C₂ = 7.00 mol/L
Answer:
A. 0.0005u
Explanation:
The mass of an electron in amu = 9.1*10-311.66*10-27=0.0005u.
Answer:
Energy is added to the particles in each change, but boiling requires more energy than melting because the attractions must be completely overcome.
Answer:
The reaction in the cold pack is an endothermic reaction
Explanation:
An endothermic reaction is a reaction that absorbs energy (heat) from the surrounding to supply the required energy of activation that allows the occurrence of the reaction
Therefore, when a reaction is endothermic, it boundary or the system where the reaction is occurring feels cold to touch
Hence, the reaction in the cold pack is an endothermic reaction.
The balanced reaction is
Ca + 2H2O → Ca(OH)2 + H2
Here this reaction can be compared with
A + BC ---> AB + C
So here one reactant (A) is accepting a group which is being given by another compound (BC) however the A is not giving any group / element or ion
So this single displacement
Similarly in the given reaction
the anion OH- is only being replaced
The element Ca accepts OH- and H2O loses the same group to form new element H2
So the correct answer is
Single replacement also known as single displacement
