Answer: 46.743%
Explanation: what is the mass percentage of silicon? 46.743%
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Answer:
Look at your periodic table
Explanation:
It tells you everything like Potasium 1 and 1 ox and 1 hydrogen
The pH of a solution at 25. 0 °C that contains 2. 95 × 10^-12 m hydronium ions is 13.5.
<h3>What is pH? </h3>
pH is defined as the concentration of the hydrogen bond which is released or gained by the species in the solution which depicts the acidity and basicity of the solution.
<h3>What is pOH? </h3>
pOH is defined as the concentration of the hydronium ion present in solution.
pOH value is inversely proportional to the value of pH.
pH value increases, pOH value decreases and vice versa.
Given,
Total H+ ions = 2.95 ×10^(-12)M
<h3>Calculation of pH</h3>
pH = -log[H+]
By substituting the value of H+ ion in given equation
= log(2.95× 10^(-12) )
= 13.5
Thus we find that the pH of a solution at 25. 0 °C that contains 2. 95 × 10^-12 m hydronium ions is 13.5.
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Answer: The pressure required is 0.474 atm
Explanation:
Boyle's Law: This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.
(At constant temperature and number of moles)
The equation is,

where,
= initial pressure of gas = 1.0 atm
= final pressure of gas = ?
= initial volume of gas = 
= final volume of gas =
(
Now put all the given values in the above equation, we get:


The pressure required is 0.474 atm