Which of the following stretches are infrared-active (i. e. show a signal in the infrared spectrum)? a. The C=C stretch of trans-2-hexene
b. The C=C stretch of cis-2-hexene
c. The C=O stretch of propanone
d. The C≡C stretch of 1-butyne
e. The C≡C stretch of 2-butyne

Which is the layer underground where all empty spaces are filled with a combination of air and water ?

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)

Which type of substance ionizes partially and gives off hydrogen ions when dissolved in water? a. strong acid b. strong base c. weak acid d. weak base