PH scale is from 1 to 14 and indicates how acidic or basic a solution is. To find pH or pOH we need to know the H⁺ ion concentration or OH⁻ concentration.
pH can be calculated using the following equation;
pH = -log[H⁺]
the H⁺ concentration of the given acid is 1.0 x 10⁻⁴ M. substituting this we can find the pH
pH = -log[1x10⁻⁴]
pH = 4
answer is 1) 4
<span>Mass of CO2 = 225.632g</span>
<span>Photoelectric effect refer to the emission of electron or free carriers when light shine into a material. According to the Rutherford model, light of any energy should be able to make electrons leave the atom and be emitted.
The energy of the emitted electrons should be related to the intensity of the light. But the energy of the electron is actually only related to the energy of the light</span>
Answer:
The limiting reactant is H₂
Explanation:
The reaction of hydrogen (H₂) and carbon monoxide (CO) to produce methanol (CH₃OH) is the following:
2H₂(g) + CO(g) → CH₃OH(g)
From the balanced chemical equation, we can see that 1 mol of CO reacts wIth 2 moles of H₂. So, the stoichiometric ratio is:
2 mol H₂/1 mol CO = 2.0
We have 500 mol of CO and 750 mol of H₂, so we calculate the ratio to establish a comparison:
750 mol H₂/500 mol CO = 1.5
Since 2.0 > 1.5, we have fewer moles of H₂ than are needed to completely react with 500 moles of CO. In fact, we need 1000 moles of H₂ and we have 750 moles. So, the limiting reactant is H₂.
As one moves across a period, from left to right, both the number of protons and electrons of a neutral atom increase. The enhancing number of electrons and protons results in a greater attraction between the electrons and the nucleus. This uplifted attraction pulls the electrons nearer to the nucleus, therefore, reducing the size of the atom.
On the other hand, while moving down a group, there is an increase in the number of energy levels. The enhanced number of energy levels increases the size of the atom in spite of the elevation in the number of protons. In the outermost energy levels, the protons get attracted towards the nucleus, however, the attraction is less due to an increase in the distance from the nucleus.
