Answer:
236.9g
Explanation:
Given parameters:
Volume of gas = 81.3L
Pressure of gas = 204kPa
temperature of gas = 95°C
Unknown:
Mass of carbondioxide gas = ?
Solution:
To solve this problem, the ideal gas law will be well suited. The ideal gas law is a fusion of Boyle's law, Charles's law and Avogadro's law.
Mathematically, it is expressed as;
PV = nRT
the unknown here is n which is the number of moles;
P is the pressure, V is the volume, R is the gas constant and T is the temperature.
convert pressure into atm
101.325KPa = 1atm
204 kPa =
= 2atm
Convert temperature to Kelvin; 95 + 273 = 368K
2 x 81.3 = n x 0.082 x 368
n =
= 5.38moles
Since the unknown is mass;
Mass = number of moles x molar mass
Molar mass of carbon dioxide = 12 + 2(16) = 44g/mol
Mass = 5.38 x 44 = 236.9g
Answer:
Half-reactions:
Cr³⁺ + 1e⁻ → Cr²⁺; Zn → Zn²⁺ + 2e⁻
Net ionic equation:
2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺
Explanation:
The Cr³⁺ is reduced to Cr²⁺:
<h3>
Cr³⁺ + 1e⁻ → Cr²⁺ -Half-reaction 1-</h3>
Zn is oxidized to Zn²⁺:
<h3>
Zn → Zn²⁺ + 2e⁻ -Half-reaction 2-</h3>
Twice the reduction of Cr:
2Cr³⁺ + 2e⁻ → 2Cr²⁺
Now this reaction + Oxidation of Zn:
2Cr³⁺ + 2e⁻ + Zn → 2Cr²⁺ + Zn²⁺ + 2e⁻
<h3>2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺ - Net ionic equation</h3>
What part of it are you confused about
In order to balance an equation, we apply the principle of conservation of mass, which states that mass can neither be created nor destroyed. Therefore, the mass of an element before and after a reaction remains constant. Here, the balanced equation becomes:
4Al + 3O₂ → 2Al₂O₃
The coefficients are 4, 3 and 2.
Answer:
polyatomic, ionic
Explanation:
unit that contains two or more atoms covalently bonded together but that has an overall charge is called a(n) polyatomic ion. Many ionic compounds contain such units.