Answer:
The concentration of KOH is 0.186 M
Explanation:
First things first, we need too write out the balanced equation between HBr and KOH.
This is given as;
KOH (aq) + HBr (aq) → KBr (aq) + H2O (l)
From the reaction above, we can tell that it takes 1 mole of KOH to react with 1 mole of HBr.
We use the acid base formular in calculating unknown concentrations. This is given as;
where;
Ca = Concentration of acid
Va = Volume of acid
Cb = Concentration of base
Vb = Volume of base
na = Number of moles of acid
nb = Number of moles of base
KOH is the base and HBr is acid.
Hence;
Ca = 0.225
Va = 35
Cb = ?
Vb = 42.3
na = 1
nb = 1
Making Cb subject of formular we have;
Cb = (0.225 * 35 * 1) / (42.3 * 1)
Cb = 0.186 M
Answer: The answer is 2.3 x 10 4's.
Answer:
97 J
Explanation:
Step 1: Given data
- Mass of the sample (m): 12 kg
- Specific heat capacity (c): 0.231 J/kg.°C (this can also be expressed as 0.231 J/kg.K)
- Initial temperature: 45 K
Step 2: Calculate the temperature change
ΔT = 80 K - 45 K = 35 K
Step 3: Calculate the heat required (Q)
We will use the following expression.
Q = c × m × ΔT
Q = 0.231 J/kg.K × 12 kg × 35 K = 97 J
Baking powder is a mixture of baking soda and a mild edible acid such as tartaric acid
Answer:
Option (3)
Explanation:
Wind energy is directly derived from the wind. In the places where wind blowing is quite frequent, there wind mills are being set up, and the turbines in it rotates due to the prevailing wind. Due to this continuous motion of turbines, it collects the wind energy and it is being transferred into electrical energy.
It is cost-effective and does not produce any kind of pollution and is completely a renewable energy, that it can generated again and again.
It does have certain drawbacks also, because <u>the area may sometime do not experience constant wind, due to which it cannot store energy. So frequent wind blowing areas are the best place to set up windmills</u>.
Thus, the correct answer is option (3)
