Answer:
23892U=23490Th +42He
Explanation:
In alpha decay, the daughter nucleus is two units less than the parent in atomic number. The mass number also decreases by 4 units. The daughter is thus found two places before the parent in the periodic table.
2BF₃ + 3Li₂SO₃ ----> B₂(SO₃)₃ + <u>6LiF
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Answer:
B carbon
Explanation
Lewis structure or dot structure is an easy way to get the bonding details of atoms in a molecule. If we talk about methane molecule carbon is central atom with four electrons that are bonded to four hydrogen atoms and each bond is single covalent bond.
Please see attached figure,
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The coefficient of performance (cop) of a refrigerator is defined as the ratio of " the work necessary to heat or cool something usefully."
The usable heating or cooling delivered to work required ratio, also known as the coefficient of performance, or COP, of a heat pump, refrigerator, as well as air conditioning system. Higher efficiency, less energy (power) usage, and thus reduced operational costs are all related to higher COPs.
Coefficient of performance formula:

where, K = Coefficient of performance,
= heat of pumps output,
= work required by the system.
It is refrigeration's coefficient of performance (COP) will always be greater than 1.
Therefore, the coefficient of performance (cop) of a refrigerator is defined as the ratio of " the work necessary to heat or cool something usefully."
To know more about coefficient of performance
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Answer:
carbon dioxide is a gas so it isn't collected over water.
Explanation:
it works for insoluble gases such as hydrogen,or gases that do not dissolve easily in water such as ammonia and chlorine are readily soluble in water and are not collected this way.
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