Answer:
The freezing of water into ice causes the cracks to widen because it occupy more space.
Explanation:
When the water change its state of liquid to solid state due to decrease in temperature, it contracts means occupy less space but when the temperature reaches to 4 degree Celsius, it starts to expand. When the temperature goes below 0 degree Celsius, it will cause more expansion and occupy more space that causes the cracks to widen.
A asystem at equilibrium stops
Answer:- C. H
Explanations:- Reduction is gain of electron. In other words we could say that decrease in oxidation number is reduction.
As per the rules, oxidation number of hydrogen in its compounds is +1(except metal hydrides) and the oxidation number of oxygen in its compounds is -2.
The oxidation number in elemental form is zero.
In
, the oxidation number of H is +1 and oxidation number of O is -2. Oxidation number of Cl in
is -1. On product side, the oxidation number of hydrogen in
is zero and in
the oxidation number of H is +1 and that of O is -2. Oxidation number of Cl in
is 0.
From above data, Oxidation number of O is -2 on both sides so it is not reduced.
Oxidation number of Cl is changing from -1 to 0 which is oxidation.
Oxidation number of H is changing from +1 to 0 which is reduction.
So, the right choice is C.H
Heat. When heat is appplied to liquid it turns into gas.
Answer:
a) Aqueous LiBr = Hydrogen Gas
b) Aqueous AgBr = solid Ag
c) Molten LiBr = solid Li
c) Molten AgBr = Solid Ag
Explanation:
a) Aqueous LiBr
This sample produces Hydrogen gas, because the H+ (conteined in the water) has a reduction potential higher than the Li+ from the salt. Therefore the hydrogen cation will reduce instead of the lithium one and form the gas.
b) Aqueous AgBr
This sample produces Solid Ag, because the Ag+ has a reduction potential higher than the H+ from the water. Therefore the silver cation will reduce instead of the hydrogen one and form the solid.
c) Molten LiBr
In a molten binary salt like LiBr there is only one cation present in the cathod. In this case the Li+, so it will reduce and form solid Li.
c) Molten AgBr
The same as the item above: there is only one cation present in the cathod. In this case the Ag+, so it will reduce and form solid Ag.