Hydrogen powered cars create less pollution than gasoline powered cars when driven. what might be a challenge to using hydrogen as a fuel?

In the reaction between a crushed antacid tablet and vinegar what gas is emitted

Water's surface tension and heat storage capacity are accounted for by its a) orbitals b) weight c) hydrogen bonds d) mass e) size

If you add 5.00 ml of 0.100 m sodium hydroxide to 50.0 ml of acetate buffer that is 0.100 m in both acetic acid and sodium acetate, what is the ph of the resulting solution? acetic acid: ka = 1.8. x 10-5