Question

Mulitple Choice please answer all 3 no need to go in Depth

One mole (mol) of glucose (molecular mass = 180 daltons) is.

	a.	180 × 1023 molecules of glucose
	b.	1 kilogram of glucose dissolved in 1 liter of solution
	c.	180 kilograms of glucose
	d.	180 grams of glucose
	e.	6.022×10 23

If the pH of a certain soda drink is 2, what is the hydrogen ion concentration in that drink?

	a.	2 M
	b.	0.2 M
	c.	0.01 M
	d.	none of the above

Which chemical group is most likely responsible for an organic molecule behaving as a base?

	a.	hydroxyl
	b.	carbonyl
	c.	amino
	d.	phosphate
	e.	methyl

Answer 1

1. The answer is d. 180 grams of glucose

The molecular formula of glucose C6H1206. It shows that six-carbon, 12 hydrogen, and 6 oxygen atoms.

Molar masses are C= 12 g/mol

                                 H=1 g/mol

                                  O=16g/mol

So 1 mole of glucose C6H1206 = (6x12) + (12x1)+ (6x16)

                                                         =72+12+96

                                                          =180 g.

2. The answer is d. None of the above.

pH is the negative log of hydrogen ion concentration.

pH =−log[H+]

if pH=2, Antilog 0.18 = 1.5

[H+]=10−2=10−2+0.18=100.18×10−2=1.513×10−2

Hydrogen ion concentration will be [H+] = 1.5×10-2M

                                                                    = 0.015M

                                                                      =0.02M.

3. The answer is c. amino

The amino group is responsible for an organic molecule to behave like a base.

Amino groups are nitrogen-containing organic bases. Amines act as a base in aqueous solution and are soluble in dilute acids. Any functional group with an unshared pair of electrons acts as a Lewis base. Phosphate is negatively charged and do not need protons. Acids don’t want protons and it is donated. A base is a proton acceptor by Bronsted-Lowry definition. A carbonyl which contains hydrogens on its alpha carbons is more acidic and not basic.