Answer:
A
Explanation:
B and D have to do with plants
and C has nothing to do with cellular resporation.
The correct answer is D. Light bulbs
Explanation:
In chemistry, halogens are a group of elements characterized for being non-metallic elements (they cannot conduct heat or electricity), and for forming salts. In terms of uses, halogens had been used mainly as part of disinfectants, as well as, in the production of light bulbs and lamps. This last application implies small quantities of halogens such as iodine are used in the mechanism of bulbs or lamps and this is a better option than other elements as it increases the life of the bulb and makes bulbs to a whither color. According to this, one use of halogens is light bulbs.
Formula of density is mass divided by volume.
Answer:-
Neon is a noble gas. Neon with an electronic configuration of 2,8 has 8 electrons in it's outermost shell or valence shell.
According to the Octet theory if an element has eight electrons in it's valence shell then it is stable and does not undergo reaction. Thus Neon does not need to react and can exist freely in nature.
Sodium with an electronic configuration of 2,8,1 has 1 electron in it's valence shell. As per octet rule, it is not stable and it must lose that 1 electron to become stable.
In order to lose that 1 electron sodium must react with other substances. Hence sodium cannot exist freely in nature.
Answer:
a) COCl₂.
b) The molecular formula is COCl₂.
Explanation:
To obtain empirical formula of phosgene you should divide elemental compositions over atomic mass of each atom, and divide these results between the smallest, thus:
C = 12,14%/12,01 = 1,01
O = 16,17%/16 = 1,01
Cl = 71,69%/35,45 = 2,02
Empirical formula:
C = 1,01/1,01 = 1
O = 1,01/1,01 = 1
Cl = 2,02/1,01 = 2
C₁O₁Cl₂ ≡ COCl₂
b) You need to find the molar mass of the empirical formula to determine the ratio of the real formula, thus:
1×C 12,01g/mol =
1×O 16 g/mol =
2×Cl 35,35g/mol = 98,91g/mol
As real molecular mass is 98,9 g/mol. The molecular formula: COCl₂
I hope it helps!