Molecular distances are usually given in nanometers (1 nm = 1 10^-9 m) or in picometers (1 pm = 1 10^-12 m). However, a commonly used unit is the angstrom, where 1 Å = 1 10^-10 m. (The angstrom unit is not an SI unit.) If the distance between the Pt atom and the N atom in the cancer chemotherapy drug cisplatin is 1.97 Å, what is the distance in nanometers?

Enter a number with the correct number of significant figures.

1 nm
What is the distance in picometers?

Enter a number with the correct number of significant figures.

2 pm

The chart shown here is a plot of the logarithm of the relative abundance of elements 1 through 36 in the solar system. (The abundances are given on a scale that gives silicon a relative abundance of 1 10⁶ [the logarithm of which is 6].)

(a) What is the most abundant metal?

1

Magnesium is most abundant, but iron is very close. Iron is most abundant, but magnesium is very close.     Silicon is in most abundance. Magnesium and iron both are equal and most in abundance.

(b) What is the most abundant nonmetal?

Answer is case sensitive.

2
(c) What is the most abundant metalloid?

Answer is case sensitive.

3
(d) Which of the transition elements is most abundant?

Answer is case sensitive.

4
(e) What halogens are included on this plot? (Select all that apply.)

5

fluorine chlorin bromine iodine astatine

(f) Which is the most abundant?

6

fluorine chlorine     bromine

Write a molecular formula for each of the following molecules. Legend: gray = carbon, light gray = hydrogen, blue = nitrogen, red = oxygen. (Type your answer using the format CO2 for CO₂.)

(a) Acetaminophen is an analgesic found in such over-the-counter drugs as Tylenol.

Answer is not case sensitive.

1
(b) Dimethyl terephthalate is one of the two molecules used to make the polymers Dacron and Mylar.

Answer is not case sensitive.

2

Your body deals with excess nitrogen by excreting it in the form of urea, NH₂CONH₂.The reaction producing it is the combination of arginine (C₆H₁₄N₄O₂) with water to give urea and ornithine (C₅H₁₂N₂O₂).

C₆H₁₄N₄O₂+H₂ONH₂CONH₂+C₅H₁₂N₂O₂

If you excrete 61 mg of urea, what quantity of arginine must have been used?

Enter a number with the correct number of significant figures.

1 g
What quantity of ornithine must have been produced?

Enter a number with the correct number of significant figures.

2 g

Balance these reactions and then classify each one as a precipitation, an acid-base reaction, or a gas-forming reaction.

(a)

Answer is not case sensitive.

1K₂CO₃(aq) +

Answer is not case sensitive.

2Cu(NO₃)₂(aq)

Answer is not case sensitive.

3CuCO₃(s) +

Answer is not case sensitive.

4KNO₃(aq)

5

precipitation reaction acid-base reaction     gas-forming reaction

(b)

Answer is not case sensitive.

6Pb(NO₃)₂(aq) +

Answer is not case sensitive.

7HCl(aq)

Answer is not case sensitive.

8PbCl₂(s) +

Answer is not case sensitive.

9HNO₃(aq)

10

precipitation reaction acid-base reaction     gas-forming reaction

(c)

Answer is not case sensitive.

11MgCO₃(s) +

Answer is not case sensitive.

12HCl(aq)

Answer is not case sensitive.

13MgCl₂(aq) +

Answer is not case sensitive.

14H₂O(l) +

Answer is not case sensitive.

15CO₂(g)

16

acid-base reaction precipitation reaction     gas-forming reaction