Answer:
Magnesium oxide
Explanation:
The substance which undergoes combustion is said to be combustible.It is called fuel. If a magnesium ribbon is heated,it starts burning. When a magnesium ribbon burns,it combines with the oxygen of air to form magnesium oxide,and liberates heat and light.
The specific heat capacity of the given substance is -0.66 J/g°C.
<u>Explanation:</u>
The heat absorbed by any substance is the product of its mass, specific heat capacity and change in temperature.
q = m × c × ΔT
m is the mass in grams
q = amount of heat released or absorbed in J
ΔT = change in temperature in °C = 5 -50 = -45°C
c = specific heat capacity in J/g°C
c = 
Plugin the values, we will get,
c = 
= -0.66 J/g°C
The answer is B. In the same direction as the force. Hope this helps :)
The reaction between the reactants would be:
CH₃NH₂ + HCl ↔ CH₃NH₃⁺ + Cl⁻
Let the conjugate acid undergo hydrolysis. Then, apply the ICE approach.
CH₃NH₃⁺ + H₂O → H₃O⁺ + CH₃NH₂
I 0.11 0 0
C -x +x +x
E 0.11 - x x x
Ka = [H₃O⁺][CH₃NH₂]/[CH₃NH₃⁺]
Since the given information is Kb, let's find Ka in terms of Kb.
Ka = Kw/Kb, where Kw = 10⁻¹⁴
So,
Ka = 10⁻¹⁴/5×10⁻⁴ = 2×10⁻¹¹ = [H₃O⁺][CH₃NH₂]/[CH₃NH₃⁺]
2×10⁻¹¹ = [x][x]/[0.11-x]
Solving for x,
x = 1.483×10⁻⁶ = [H₃O⁺]
Since pH = -log[H₃O⁺],
pH = -log(1.483×10⁻⁶)
<em>pH = 5.83</em>