Answer:
pH = 1.32
Explanation:
H₂M + KOH ------------------------ HM⁻ + H₂O + K⁺
This problem involves a weak diprotic acid which we can solve by realizing they amount to buffer solutions. In the first deprotonation if all the acid is not consumed we will have an equilibrium of a wak acid and its weak conjugate base. Lets see:
So first calculate the moles reacted and produced:
n H₂M = 0.864 g/mol x 1 mol/ 116.072 g = 0.074 mol H₂M
54 mL x 1L / 1000 mL x 0. 0.276 moles/L = 0.015 mol KOH
it is clear that the maleic acid will not be completely consumed, hence treat it as an equilibrium problem of a buffer solution.
moles H₂M left = 0.074 - 0.015 = 0.059
moles HM⁻ produced = 0.015
Using the Henderson - Hasselbach equation to solve for pH:
ph = pKₐ + log ( HM⁻/ HA) = 1.92 + log ( 0.015 / 0.059) = 1.325
Notes: In the HH equation we used the moles of the species since the volume is the same and they will cancel out in the quotient.
For polyprotic acids the second or third deprotonation contribution to the pH when there is still unreacted acid ( Maleic in this case) unreacted.
Answer:
1 It gives the cell its structure
2 It regulates the materials that enter and leaves the cell
Answer :
- Nuclear fission : In nuclear reaction, the nucleus of a larger atom breaks into two or more smaller nuclei. In fission process, protons and neutrons are produced and larger amount of energy is released.
Example : In nuclear power plant, the energy released from the process of nuclear fission which is converted into electrical energy that is used in our homes and factories.
- Nuclear fusion : In nuclear reaction, the nuclei of two or more smaller atoms combine together to form single larger molecule. In fusion process, the mass of the resulting nuclei is more as compared to the starting nuclei and large amount of energy is also released.
Example : This process occurs in the sun and stars. In this, the isotopes of Hydrogen, Tritium and Deuterium combine together to form a neutron and a helium atom under high pressure and temperature.
Answer:
4.767 grams of KCl are produced from 2.50 g of K and excess Cl2
Explanation:
The balanced equation is
2 K+ Cl2 --->2 KCI
Here the limiting agent is K. Hence, the amount of KCl will be calculated as per the mass of 2.50 gram of K
Mass of one atom/mole of potassium is 39.098 grams
Number of moles is 2.5 grams = 
So, 2 moles of K produces 2 moles of KCL
0.064 moles of K will produces 0.064 moles of KCl
Mass of one molecule of KCl is 74.5513 g/mol
Mass of 0.064 moles of KCl is 4.767 grams
The answer to you’re question is C. NH3
