Answer:
A pH less than 7 indicates an acidic solution and a pH greater than 7 indicates a basic solution. Ultimately, the pH value indicates how much H+ has dissociated from molecules within a solution. The lower the pH value, the higher concentration of H+ ions in the solution and the stronger the acid.
Explanation:
N/A
Answer is: 3,94 of hydrogen gas.
Chemical reaction: 2K + 2HBr → 2KBr + H₂.
n(K) = 9,87 mol.
n(H₂) = ?.
from reaction: n(K) : n(H₂) = 2 : 1.
9,87 mol : n(H₂) = 2 : 1
n(H₂) = 4,935 mol for 100% yield of reaction
n(H₂) = 4,935 · 0,798 = 3,94 mol for 78,9 % yield of reaction.
n - amount of substance
Answer:
140. J/g*K
Explanation:
To find the specific heat capacity, you need to use the following equation:
Q = mcΔT
In this equation,
-----> Q = energy/heat (J)
-----> m = mass (g)
-----> c = specific heat (J/mole*K)
-----> ΔT = change in temperature (K)
Before you can use the equation above, you need to (1) convert kg to grams, then (2) convert grams to moles (via molar mass), and then (3) convert Celsius to Kelvin. The final answer should have 3 significant figures.
1.11 kg C₄H₈O₂ x 1,000 = 1110 g
Molar Mass (C₄H₈O₂): 4(12.01 g/mol) + 8(1.008 g/mol) + 2(16.00 g/mol)
Molar Mass (C₄H₈O₂): 88.104 g/mol
1110 grams C₄H₈O₂ 1 mole
------------------------------ x ------------------------- = 12.6 moles C₄H₈O₂
88.104 grams
34.5 °C + 273 = 307.5 K
52.3 °C + 273 = 325.3 K
Q = mcΔT <----- Equation
3.14 x 10⁴ J = (12.6 moles)c(325.3 K - 307.5 K) <----- Insert values
3.14 x 10⁴ J = (12.6 moles)c(17.8) <----- Subtract
3.14 x 10⁴ J = (224.28)c <----- Multiply 12.6 and 17.8
140. = c <----- Divide both sides by 224.28
**this answer may be slightly off due to using different molar masses/Kelvin conversions**