Answer:
The pH value of the mixture will be 7.00
Explanation:
Mono and disodium hydrogen phosphate mixture act as a buffer to maintain pH value around 7. Henderson–Hasselbalch equation is used to determine the pH value of a buffer mixture, which is mathematically expressed as,
![pH=pK_{a} + log(\frac{[Base]}{[Acid]})](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%20%2B%20log%28%5Cfrac%7B%5BBase%5D%7D%7B%5BAcid%5D%7D%29)
According to the given conditions, the equation will become as follow
![pH=pK_{a} + log(\frac{[Na_{2}HPO_{4} ]}{[NaH_{2}PO_{4}]})](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%20%2B%20log%28%5Cfrac%7B%5BNa_%7B2%7DHPO_%7B4%7D%20%5D%7D%7B%5BNaH_%7B2%7DPO_%7B4%7D%5D%7D%29)
The base and acid are assigned by observing the pKa values of both the compounds; smaller value means more acidic. NaH₂PO₄ has a pKa value of 6.86, while Na₂HPO₄ has a pKa value of 12.32 (not given, but it's a constant). Another more easy way is to the count the acidic hydrogen in the molecular formula; the compound with more acidic hydrogens will be assigned acidic and vice versa.
Placing all the given data we obtain,
The reaction between K₂SO₄(aq) and SrI₂(aq) produces KI(aq) and SrSO₄(s) as products.
The reaction is
K₂SO₄(aq) + SrI₂(aq) → KI(aq)+ SrSO₄(s)
To balance the equation both side of the reaction should have same number of atoms in each element.
Right hand side of the reaction has 1 K, 1 I, 1 Sr, 1 S and 4 O atoms while 2 K, 2 I, 1 Sr,1 S and 4 O present in left hand side of the reaction.
Hence, number of I atoms and number of K atoms are not balanced.
To balance the K atoms we should add 2 before KI. Then I atoms will be 2 at the right hand side.
Hence, the balanced reaction equation is
K₂SO₄(aq) + SrI₂(aq) → 2KI(aq)+ SrSO₄(s)
Answer:
Explanation:
THE PHOTOCHEMICAL(LIGHT) REACTIONS :This is a phase of photosynthesis where sunlight is used as a source of energy to manufacture two chemical compounds which are "Reduced nicotinamide adenine dinucleotide phosphate"-NADPH and "Adenosine triphosphate"-ATP.This phase of photosynthesis involves 4 steps or reactions which are :
STEP 1 : Activation or Energization of chlorophyll - In this reaction,chlorophyll molecules in green algae or plants absorb sunlight and become activated,that is the electrons of the chlorophyll molecule acquire solar energy and become excited.
STEP 2 : PHOTOLYSIS OF WATER - Here the energy absorbed by the chlorophyll molecules are used to split water molecules into H+ ions and OH-- ions.
STEP 3:Formation of NADPH -The hydrogen ions (H+) produced reacts with an NADP ( an electron carrier in the chlorophyll) to form NADPH.
STEP 4: FORMATION OF ATP - The high energy generated from the electron transfer process or chain is used to add a phosphate group to ADP (Adenosine dphosphate) to form ATP.
DARK PHASE :In this phase of photosynthesis,the NADPH generated in the light phase is used as a reducing equivalent to reduce CO2 to form Glucose (food) using the ATP generated as a source of energy.
The atomic number of an element gives the proton and electron in the atom while the mass number gives the total number of protons and neutron
