A, because the number of valence shell electrons (outer shell electrons) tells us how much the element or compound wants to bond or give up electrons. Most compounds and elements want to have eight valence ectrons in it's outer ring. So if an atom is far away from having eight, it will want to react more often.
Answer:
A.
Explanation:
It would be A. because the question is asking how the harmful chemicals have an effect on the environment. This answer also proves that even though we don't mean to harm the environment it still happens because we are using these chemicals for things in our daily life.
<span>That would be compound!
Compounds are pure substances, which consists of two or more elements chemically combined in a fixed proportion by mass. Compounds have definite proportion.</span>
Answer:
S²⁻(aq) + Cr²⁺(aq) ⇄ CrS(s)
Explanation:
The molecular equation includes all the species in the molecular form. Usually, it is useful to write this first to balance the equation. This is a double displacement reaction.
K₂S(aq) + Cr(NO₃)₂(aq) ⇄ 2 KNO₃(aq) + CrS(s)
The full ionic equation includes all ions and the species that no dot dissociate in water.
2 K⁺(aq) + S²⁻(aq) + Cr²⁺(aq) + 2 NO₃⁻(aq) ⇄ 2 K⁺(aq) + 2 NO₃⁻(aq) + CrS(s)
The net ionic equation includes only those ions that participate in the reaction and the species that do not dissociate in water.
S²⁻(aq) + Cr²⁺(aq) ⇄ CrS(s)
Moles of gas = 0.123
<h3>Further explanation</h3>
In general, the gas equation can be written

where
P = pressure, atm , N/m²
V = volume, liter
n = number of moles
R = gas constant = 0.082 l.atm / mol K (P= atm, v= liter),or 8,314 J/mol K (P=Pa or N/m2, v= m³)
T = temperature, Kelvin
Volume(V) =2.5 L
Pressure(P) = 1.2 atm
Temperature(T) = 25 + 273=298 K
