HCOOH, CO

CH₃COOH, CO

CH₃COOH, CO₂

HCOOH, CO₂

CH₃CHO    +   H₂O

HCHO    +   H₂O

CH₃CH₂COCH₃    +  H₂O

CH₃COCH₃    +   H₂O

the low K_a value for strong acids

the low percent ionization of strong acids

the more complex atomic structures of strong acids

the incomplete ionization of weak acids

A lower pH in the mouth inhibits the growth of bad bacteria which eventually leads to tooth decay.

A higher pH in the mouth inhibits the growth of bad bacteria which eventually leads to tooth decay.

A higher pH in the mouth promotes the growth of bad bacteria which eventually leads to tooth decay.

A lower pH in the mouth promotes the growth of bad bacteria which eventually leads to tooth decay.

₂₄Cr, ₂₂Ti, ₂₆Fe, ₂₈Ni, ₂₅Mn

₁₂Mg, ₂₂Ti, ₂₀Ca, ₁₃Al

₁₁Na, ₂₄Cr, ₃Li, ₁₂Mg,

₂₄Cr, ₃Li, ₁₂Mg, ₂₂Ti

The K_w increases and the pH increases

The K_w decreases and the pH increases

The K_w decreases and the pH decreases

The K_w increases and the pH decreases

More energy is released when two HI bonds are formed than is used when the H–H and   I–I bonds are broken.

Energy is released when H–H and I–I bonds are broken.

The bond energies of the reactants are larger than the bond energies of the products.

The products are at a higher energy level than the reactants.

The colour of solution will become colourless.

No change in colour of solution.

The colour of solution will become paler.

The colour of solution will become more intense.

explosion, nuclear reaction

degradable of plastic, formation of coal

decay of building and car by acid rain

rusting of iron and weathering of rocks