Chemistry questions

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1. Which of the following concentrations indicates a basic solution?

(A) [H3O+]=5∗10−7M
(B) [H3O+]=5∗10−10M
(C) [OH−]=[H3O+]
(D) [OH−]=6.8∗10−9M

2. What acid-base definition describes a compound that accepts an electron pair?

(A) Lewis acid
(B) Lewis base
(C) Arrhenius acid
(D) Brønsted-Lowry base

3. Hydrochloric acid (HCl) is which of the following?

(A) A strong acid
(B) A strong base
(C) A neutral salt
(D) A weak acid
(E) A weak base

4. How does the Brønsted-Lowry theory of acids and bases describe acids?

(A) Brønsted-Lowry acids are proton acceptors when dissolved in water
(B) Brønsted-Lowry acids are electron acceptors when dissolved in water
(C) Brønsted-Lowry acids are proton donors when dissolved in water
(D) Brønsted-Lowry acids are acids that dissociate 100% in a solution
(E) Brønsted-Lowry acids are any compound that dissociates in water to yield a proton

5. By definition, a Lewis base is any species that __.

(A) accepts a pair of electrons from a Lewis acid
(B) donates a pair of electrons to a Lewis acid
(C) always produces a gas as a product
(D) removes hydrogens from a solution
(E) has a pH below 7

6. All acids have which phase label?


(A) (l)
(B) (s)
(C) (aq)
(D) (g)

7. According to the Lewis definition, acids are __.

(A) hydrogen donors
(B) electron pair donors
(C) hydrogen acceptors
(D) electron pair acceptors
(E) hydroxide acceptors

8. What is the Lewis definition of bases?

(A) increase the concentration of hydroxide ions in a solution
(B) electron pair acceptors
(C) increase the concentration of hydrogen ions in a solution
(D) electron pair donors
(E) accept hydrogen ions

9. What does amphoteric mean?

(A) A substance cannot act as an acid or a base
(B) A substance that is highly acidic
(C) A substance has a high concentration of neutrons
(D) A substance can act either as an acid or a base
(E) A substance is highly basic

10. What is a diprotic acid?

(A) An acid with 1 ionizable hydrogen
(B) A really strong base
(C) An acid with 2 ionizable hydrogens
(D) An acid with 3 ionizable hydrogens
(E) A really weak base

Don't just look, try them out too!

🌟Important Increasing Orders

1️⃣ Ionization Energy

(i) Na, Al, Mg, Si
(ii) Li, B, Be, C, O, N, F, Ne, He (Ist I.P.)
(iii) Be, C, B, N, F, O, Ne, He, Li (IInd I.P.)

2️⃣ Electron Affinity

(i) I, Br, F, Cl
(ii) Cu, Ag, Au (EA, of Au is very high = 222 kJ mol–1)
(iii) O, S, F, Cl
(iv) N, P, O, S

3️⃣ Electronegativity

(i) As, P, S, Cl
(ii) I, Br, Cl, F
(iii) C, N, O, F

4️⃣ Oxyacids Of Halogen

1. Hypochlorous acid- HClO
2. Chlorous acid - HClO2
3. Chloric acid - HClO3
4. Perchloric acid - HClO4

5️⃣ Acidic  Strength

HClO < HClO2 < HClO3 < HClO4

6️⃣ Oxidising Nature

HClO > HClO2 > HClO3 > HClO4

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