The pH of salt depends on the component acid and base that comprise them. For example, if the salt is made up of strong acid and weak base then, the salt is acidic. If the salt is formed from strong base and weak acid then, the salt is basic. For this item, NH4Cl is acidic and also Ca(NO3)2 is acidic.
Answer:
29.42 Litres
Explanation:
The general/ideal gas equation is used to solve this question as follows:
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas law constant (0.0821 Latm/molK)
T = temperature (K
According to the information provided in this question;
mass of nitrogen gas (N2) = 25g
Pressure = 0.785 atm
Temperature = 315K
Volume = ?
To calculate the number of moles (n) of N2, we use:
mole = mass/molar mass
Molar mass of N2 = 14(2) = 28g/mol
mole = 25/28
mole = 0.893mol
Using PV = nRT
V = nRT/P
V = (0.893 × 0.0821 × 315) ÷ 0.785
V = 23.09 ÷ 0.785
V = 29.42 Litres
Answer is: pH value of weak is 3.35.
Chemical reaction (dissociation): HA(aq) → H⁺(aq) + A⁻(aq).
c(HA) = 0.0055 M.
α = 8.2% ÷ 100% = 0.082.
[H⁺] = c(HA) · α.
[H⁺] = 0.0055 M · 0.082.
[H⁺] = 0.000451 M.
pH = -log[H⁺].
pH = -log(0.000451 M).
pH = 3.35.
pH (potential of
hydrogen) is a numeric scale used to specify the acidity or basicity <span>an aqueous solution.</span>
Answer : The molecular weight of a gas is, 128.9 g/mole
Explanation : Given,
Density of a gas = 5.75 g/L
First we have to calculate the moles of gas.
At STP,
As, 22.4 liter volume of gas present in 1 mole of gas
So, 1 liter volume of gas present in 
mole of gas
Now we have to calculate the molecular weight of a gas.
Formula used :
Now put all the given values in this formula, we get the molecular weight of a gas.
Therefore, the molecular weight of a gas is, 128.9 g/mole
The study of matter and energy best describes physical science. Hence, option B is correct.
<h3>What is physical science?</h3>
Physical science is the study of the inorganic world.
Physics is a branch of science that studies matter and its motion through space and time, along with related concepts such as energy and force. Physics is one of the "fundamental sciences" because of the other natural sciences (like biology, geology etc.)
Thus the study of matter and energy best describes physical science. Hence, option B is correct.
Learn more about the physical science here:
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