The answer is D. Heating the air in the can reduces the air pressure in the can. When the can is inverted in a pan with cold water, the can collapses inwards. This is because the cold water cooled the air around the outside of the can. Cold air has a higher pressure that hot air because it’s denser. Became. The higher air pressure outside presses on the can walls and force them inwards.
b. 17
c. 18
d. 19
Answer:
protons: 36
neutrons:48
electrons:36
Explanation:
the number of protons in an element is = to the atomic # (36)
the number of neutrons is the atomic mass - atomic # (84-36=48)
In a neutral charged element the # of protons = # of electrons
B. molecular number.
C. valence.
D. atomic number
The correct answer is:
C. valence.
Explanation:
The valence or valency of an element is a stratagem of its connecting power with other atoms when it makes chemical compounds or molecules.
A valence electron is an outer shell electron that is connected with an atom, and that can compete in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond provide one valence electron in order to form a shared pair
Answer:
C. valence
Explanation:
The valence or valency of an element is a stratagem of its connecting power with other atoms when it makes chemical compounds or molecules.
A valence electron is an outer shell electron that is connected with an atom, and that can compete in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond provide one valence electron in order to form a shared pair.
Answer:
Molarity of NaOH solution is 1.009 M
Explanation:
Molar mass of HCl is 36.46 g/mol
Number moles = (mass)/(molar mass)
So, 0.8115 g of HCl = HCl = 0.02226 moles HCl
1 mol of NaOH neutralizes 1 mol of HCl.
So, if molarity of NaOH solution is S(M) then moles of NaOH required to reach endpoint is
So,
or, S = 1.009
So, molarity of NaOH solution is 1.009 M
The statement that is given above “When a system performs work on the surroundings, the work is reported with a negative sign” is true. When the surrounding performs work by the system, it is positive.