Answer: 12g
Explanation:
The amount of energy (Q) required to raise the temperature of a substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Given that:
Q = 216 joules
Mass of aluminium = ? (let unknown value be Z)
C = 0.90 JºC-1g-1
Φ = (Final temperature - Initial temperature)
= 35°C - 15°C = 20°C
Then, Q = MCΦ
216 J = Z x 0.90 JºC-1g-1 x 20°C
216 J = Z x 18 J°g-1
Z = (216J/18 J°g-1)
Z = 12g
Thus, the mass of the aluminium is 12grams
Remember that
- For being a bond covalent ∆E<1.8
- For being a bond ionic ∆E>1.8
#1
Carbon is present so it's covalent
#2
#3
- P-H will hardly form a bond
#4
#5
The substance doesn't have a specific name. We just say that that substance is being reduced. Remember this mnemonic - OILRIG where "Oxidation is Loss, Reduction is Gain" of electrons.
Answer is: household ammonia has 10 times higher H⁺ concentration.
1) pH(household ammonia) = 11.5.
pH = -log[H⁺], approximately the negative of the base 10 logarithm of the molar concentration of hydrogen ions.
[H⁺] = 10∧(-pH).
[H⁺] = 10∧(-11.5).
[H⁺] = 3.16·10⁻¹² M; concentration of hydrogen ions.
2) pH(household bleach) = 12.5.
[H⁺] = 10∧(-12.5).
[H⁺] = 3.16·10⁻¹³ M.
3) 3.16·10⁻¹² M / 3.16·10⁻¹³ M = 10.
