By use of ideal gas equation PV= nRT where n is the number of moles,P = pressure, V = volume, R= gas constant (0.08206 L. atm/ mol.k) ant T is the temperature,
to calculate the number of moles(n) =PV/RT
convert ml to L, that is 200/1000= 0.2 L
convert mmHg to atm, that is 780mm hg x 1atm/ 760 mm hg= 1.026 atm
convert temperature to kelvin, that is 135 +273= 408 k
n is therefore= (0.2 x 1.026)/ ( 0.08206 x 408)= 6.129 x10^-3 moles
from avogadro constant 1moles = 6.02 x10^23 molecules what about 6 .129 x10^-3 moles
= ( 6.02 x10^23) x (6.129 x10^-3)/ 1mole = 3.69 x10^21 molecules
Answer:
c. Cr
Explanation:

The compound is containing
ion.
If acid reacts with it, CO_2 evolves.

therefore, Cr would form a precipitate when added to an aqueous solution of this compound. Cr2CO3 is the precipitate.
They will have no air and no energy or food. No food for animals, so animals die, and humans die with the lack of food, meat and plants
Answer: The sample of wine could be described as numbers 1, 3 & 4
Explanation:
It is a mixture because it is the physical combination of two or more substances
It is a homogeneous mixture because any solid, liquid, or gaseous mixture that has the same proportions of its components throughout any given sample is regarded as a homogeneous mixture
It is a solution because it is a special type of homogeneous mixture composed of two or more substances
Electrolytes are substances which are capable of producing a solution that has the ability to conduct electricity. These electrolytes are formed from the dissociation of salts into ions. The positive ions are named cations while the negative ions are termed anions.
Hence, the answer to these item is SALT. Salt are substances produced by the reaction of cations and anions.