It is false. The salt bridge is not a path for electrons, but a path for ions to flow from one half-cell to another. It help to balance the charge between the oxidation and reduction vessels.
When it changes phases energy is needednto break down the bonds so that is can change state from one phase to another.
A for the first and b for the second!!:))
Answer:
half lives passed=5
given sample=90g
sample left=2.8125g
Explanation:
no. of half lives=total time/half life
no.=19days/3.8days
no.=5 days
after 5 half lives sample left=2.8125g
Answer:
236 g/mol
Explanation:
This question is asking to calculate the molar mass/formula mass of calcium nitrate tetrahydrate with the chemical formula: Ca(NO3)2 · 4H20. This is done as follows:
Atomic mass of the constituent elements are as follows:
Ca = 40
N = 14
O = 16
H = 1
Hence, in Ca(NO3)2 · 4H20.
= 40 + {14 + 16(3)}2 + 4 {1(2) + 16}
= 40 + {14 + 48}2 + 4{2 + 16}
= 40 + {62}2 + 4{18}
= 40 + 124 + 72
= 236
Hence, the molar mass of Ca(NO3)2 · 4H20 is 236g/mol.