Explanation: A pure substance is defined when a substance has a single type of molecule. If more than 1 type of molecule is present in a substance, then it is considered as a mixture.
Soda is basically a mixture of water and carbon dioxide. More than 1 type of molecule is present.
Gasoline is a mixture of may gases. More than 1 type of molecule is present.
Salt water contains salt and water molecules, hence it is considered as a mixture.
Carbon dioxide has only 1 type of molecule which is molecules. Hence, it is a pure substance.
The empirical formula of ribose (a sugar) is CH2O. In a separate experiment, using a mass spectrometer, the molar mass of ribose was determined to be 150 g/mol.Explanation:
<span>The pH is given by the Henderson - Hasselbalch equation:
pH = pKa + log([A-]/[HA]) pH = -log(</span><span>1.3 x 10^-5) + log(0.50/0.40) pH = 4.98 The answer to this question is 4.98. </span>