Acids and Bases part 1

Which statement is true for ALL aqueous solutions of acids?

• They have a pH value greater than 7.

• They react with copper to give hydrogen gas.

• They react with magnesium carbonates to give CO_2^.

• They react with ammonium chloride to produce ammonia.

Malonic acid is an acid commonly used to flavor foods.

Which statement about malonic acid is INCORRECT?

• It turns moist blue litmus paper red.

• It releases hydrogen ions (H⁺) when dissociated in water.

• It reacts with calcium hydroxide to form a salt and hydrogen gas.

• An aqueous solution of malonic acid can conduct electricity.

What test should be used to detect hydrogen gas?

• Glowing splint test

• Lighted splint test

• Bubbling into limewater

• Turning damp blue litmus paper red

Pairs of substances are listed below.

In which option will BOTH substances react with sulfuric acid to produce gas?

• Solid copper and magnesium oxide

• magnesium sulfate and solid sodium

• potassium carbonate and solid carbon

• ammonium carbonate and solid iron

What will be observed when CO₂ is bubbled into aqueous calcium hydroxide?

• Nothing

• Effervescence (bubbles)

• White precipitate

• Colorless solution turns white

Which option shows the correct relative reactivities of metals in DESCENDING order, i.e., most reactive to least reactive?

• Pb, Na, Cu, Ag

• Fe, Zn, Mg, Na

• K, Ca, Mg, Fe

• Na, K, Ca, Mg