The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2
The answer would be 371 because it has multiple complete digits
Mary thinking her astrological sign, Leo, is a perfect fit for her personality is a belief in pseudoscience because there is not scientific evidence confirming such beliefs.
The answer is the second option.
Aqueous solutions of barium nitrate and potassium phosphate are mixed.
What is the precipitate and how many molecules are formed?
Barium nitrate has a chemical symbol of Ba(NO3)2 and potassium phosphate
has a chemical symbol K2PO4. The reaction between these two is a double
replacement reaction yielding barium phosphate and potassium nitrate.
The chemical equation representing the reaction is,
Ba(NO3)2 + K2PO4 à KNO3 +
BaPO4
Answer:
Ba(ClO₃)₂ → BaCl₂ + 3 O₂ <em>Descomposition. </em>
CaO + CO₂ → CaCO₃ <em>Combination. </em>
NaNO₂ + HCl → NaCl + HNO₂ <em>Double replacement. </em>
Mg + ZnSO₄ → MgSO₄ + Zn <em>Single replacement. </em>
Explanation:
A combination reaction is defined as a reaction in which two or more substances combine to form a single new substance.
A + B → AB
A descomposition reaction is defined as a reaction in which a compound breaks down into two or more simpler substances.
AB → A + B
A double replacement is a chemical reaction were the positive and negative ions of two ionic compounds exchange places to form two new compounds.
AB + CD → AD + CB
A single replacement is another type of reaction were one element replaces a similar element in a compound.
A + BC → AC + B
Thus, with this information it is possible to classify these reactions as:
Ba(ClO₃)₂ → BaCl₂ + 3 O₂ <em>Descomposition. </em>One single molecule breaks down into two or more molecules
CaO + CO₂ → CaCO₃ <em>Combination. </em>Two substances are combined to form one single molecule
NaNO₂ + HCl → NaCl + HNO₂ <em>Double replacement. </em>Na and H are exchange places to form two new compounds
Mg + ZnSO₄ → MgSO₄ + Zn <em>Single replacement. </em>Mg is replacing Zn.
I hope it helps!
