Mass number minus atomic number equals neutrons.
234-92=142
Answer:
The answer to your question is letter b) He and Ne
Explanation:
Elements that have similar properties are placed in the same group in the periodic table.
So
A C and F These elements do not have similar properties because C is in group 4A and F is in group 7A. This is not the right answer.
B He and Ne These elements have similar properties becase they are in the same group (8A).
C Al and Si These elements do not have similar properties because Al is in group 3A and Si is in group 4A. This is not the right answer.
D N and S These elements do not have similar properties because N is in group 5A and S is in group 6A. This is not the right answer.
<span>The correct answer is letter A. 1.5 VDC. A standard dry cell has an output voltage of A. 1.5 VDC. Standard dry cell is a type of electricity-producing chemical cell, that is commonly use in households, and even portable devices. Dry cell is zinc-carbon cell and with nominal voltage of 1.5 volts.</span>
When ketone is reacted with phosphorous pentachloride, chlorination takes place at the carbonyl carbon with substitution of the oxygen atom to give a geminal dichloride (with 2 Cl atoms on same carbon) according to the following equation:
so we can say that acetone is converted into 2,2-dichloropropane by action of PCl₅
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