142 kg in grams:
1 kg ---------- 1000 g
142 kg -------- ?
142 x 1000 / 1 => 142000 g
Atomic mass Cu = 63.54 a.m.u
Therefore:
63.54 g ------------ 6.02x10²³ atoms
142000 g --------- ??
142000 x ( 6.02x10²³) / 63.54 =
8.54.10²⁸ / 63.54 => 1.34.10²⁷ atoms of Cu
Answer:
The new volume of the gas when the pressure is changed to 2.84 atm is 822.82 mL.
Explanation:
Boyle's law says that "The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure." That is, if the pressure increases, the volume decreases, while if the pressure decreases, the volume increases.
Boyle's law is expressed mathematically as:
Pressure * Volume = constant
or
P * V = k
Assuming that you have a certain volume of gas V1 that is at a pressure P1 at the beginning of the experiment, by varying the volume of gas to a new value V2, then the pressure will change to P2, and it will be fulfilled:
P1*V1= P2*V2
In this case:
- P1= 9.86 atm
- V1= 237 mL
- P2= 2.84 atm
- V2=?
Replacing:
9.86 atm* 237 mL= 2.84 atm*V2
and solving you get:

V2= 822.82 mL
<u><em>The new volume of the gas when the pressure is changed to 2.84 atm is 822.82 mL.</em></u>
Answer:
to change an atom labeled + ion or -ion into a neutral atom, an electron is either added or removed from it
Answer:
radiant - chemical is the best answer
Answer:
Option (A) Each Zn atom loses 2 electrons, and each Co2+ ion gains 2
Explanation:
To know the right answer to the question, let us observe the changes in the oxidation number of Zn and Co. This is illustrated below:
Zn(s) + Co2+(aq) → Zn2+(aq) + Co(s)
The oxidation number of Zn changes from 0 to +2 indicating that Zn has lose 2 electrons.
The oxidation number of Co changes from +2 to 0 indicating that Co has gain 2 electrons.
Therefore, option A is the correct answer.