The elements in each pair have in common it that they are metaloids
Answer:
12.99
Explanation:
<em>A chemist dissolves 716. mg of pure potassium hydroxide in enough water to make up 130. mL of solution. Calculate the pH of the solution. (The temperature of the solution is 25 °C.) Be sure your answer has the correct number of significant digits.</em>
Step 1: Given data
- Mass of KOH: 716. mg (0.716 g)
- Volume of the solution: 130. mL (0.130 L)
Step 2: Calculate the moles corresponding to 0.716 g of KOH
The molar mass of KOH is 56.11 g/mol.
0.716 g × 1 mol/56.11 g = 0.0128 mol
Step 3: Calculate the molar concentration of KOH
[KOH] = 0.0128 mol/0.130 L = 0.0985 M
Step 4: Write the ionization reaction of KOH
KOH(aq) ⇒ K⁺(aq) + OH⁻(aq)
The molar ratio of KOH to OH⁻is 1:1. Then, [OH⁻] = 0.0985 M
Step 5: Calculate the pOH
We will use the following expression.
pOH = -log [OH⁻] = -log 0.0985 = 1.01
Step 6: Calculate the pH
We will use the following expression.
pH + pOH = 14
pH = 14 - pOH = 14 -1.01 = 12.99
Weight=mass×g=10×9.8=98N
<span>hope it helped :-)</span>
Answer:
Increase in height from the ground.
Explanation:
Potential energy =mass×acceleration due to gravity×height.
P.E= mgh
The relation between the volume and the temperature of the gas is given by Charles's law. The final temperature of the gas at 0.75 liters is -193.8°C.
<h3>What is Charles's law?</h3>
Charles's law was derived from the ideal gas equation and is used to state the relationship between the temperature and the volume of the gas. With a decrease in volume the temperature decreases.
If the pressure is kept constant then with an increase in temperature the volume of the gas expands. The law is given as,
V₁ ÷ T₁ = V₂ ÷ T₂
Given,
Initial volume (V₁) = 2.80 L
Initial temperature (T₁) = 23 °C = 296.15 K
Final volume (V₂) = 0.75 L
Final temperature = T₂
Substituting the values above as:
T₂ = (V₂ × T₁) ÷ V₁
= 0.75 × 296.15 ÷ 2.80
= 79.325 K
Kelvin is converted as, 79.325K − 273.15 = -193.8°C
Therefore, the final temperature is -193.8°C.
Learn more about Charle's law, here:
brainly.com/question/16927784
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