The number above the symbol is the atomic mass (or atomic weight). This is the total number of protons and neutrons in an atom. The number below the symbol is the atomic number and this reflects the number of protons in the nucleus of each element's atom. Every element has a unique atomic number.
Answer:
The order of elements by volume-fraction (which is approximately molecular mole-fraction) in the atmosphere is nitrogen (78.1%), oxygen (20.9%), argon (0.96%), followed by (in uncertain order) carbon and hydrogen because water vapor and carbon dioxide, which represent most of these two elements in the air, are variable.
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Answer: Option C. p-dichlorobenzene and 1,4-dichlorobenzene.
Explanation:
A line-angle formula with six vertices and a circle inscribed corresponds to the compound known as benzene.
Further, according to the IUPAC standards for naming benzene derivatives, you must first number the position of the substituent. In this case, the substituents (chloros) are located at the positions 1 and 4; also, for the benzene derivatives when they have 2 substituents and the positions are 1 and 4, this configuration is known as <em>para </em>or <em>p </em>configuration.
Additionally, this compound has 2 substituents (chloros) so you have to indicate this number (di).
Therefore, the correct answer is C. p-dichlorobenzene and 1,4-dichlorobenzene.
Answer:
B) Iron (c=0.45 J/g°C)
Explanation:
Given that:-
Heat gain by water = Heat lost by metal
Thus,
Where, negative sign signifies heat loss
Or,
For water:
Mass = 120 g
Initial temperature = 21.8 °C
Final temperature = 24.5 °C
Specific heat of water = 4.184 J/g°C
For metal:
Mass = 40.2 g
Initial temperature = 99.3 °C
Final temperature = 24.5 °C
Specific heat of metal = ?
So,
<u>This value corresponds to iron. Thus answer is B.</u>
