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Answer:
0.11mol/dm³
Explanation:
The reaction expression is given as:
HCl + NaOH → NaCl + H₂O
Volume of acid = 25cm³ = 0.025dm³
Volume of base = 18.4cm³ = 0.0184dm³
Concentration of base = 0.15mol/dm³
Solution:
The concentration of hydrochloric acid = ?
To solve this problem, let us first find the number of moles of the base;
Number of moles = concentration x volume
Number of moles = 0.15mol/dm³ x 0.0184dm³ = 0.00276mol
From the balanced reaction equation;
1 mole of NaOH will combine with 1 mole of HCl
Therefore, 0.00276mol of the base will combine with 0.00276mol of HCl
So;
Concentration of acid =
=
= 0.11mol/dm³
Answer:
1.50 g
Explanation:
The heat absorbed by the aluminum in this case is:
q = m x C x ΔT m= q/ (C x ΔT)
q= 9.86 J
C = 0.90 J/g-K
ΔT = ( 30.5 ºC - 23.2 ºC ) = 7.3 ºC = 7.3 K (this is a range of temperature)
m = 9.86 J / ( 0.90 J/g-K ) x 7.3 K ) = 1.50 g
Answer:
<h2>0.52 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula

From the question
volume = final volume of water - initial volume of water
volume = 35 - 8 = 27 mL
We have

We have the final answer as
<h3>0.52 g/mL</h3>
Hope this helps you
Answer:
No one is correct. The correct expression is:
Keq = [H₂]² . [O₂]² / [H₂O]²
Explanation:
To build the Keq expression in a chemical equilibrium you must consider the molar concentrations of reactants / products, and they must be elevated to the stoichiometric coefficient.
The balance reaction is:
<u>2</u> H₂O (g) ⇄ <u>2</u> H₂ (g) + O₂ (g)
Keq = [H₂]² . [O₂] / [H₂O]²
In opposite side: <u>2</u> H₂ (g) + O₂ (g) ⇄ <u>2</u> H₂O (g)
Keq = [H₂O]² / [H₂]² . [O₂]