CHEM 1010 Homework 2

Predict the chemical formula for the ionic compound formed by NH₄⁺ and PO₄³⁻

(NH₄)₃PO₄

Determine the number of protons (p) and electrons (e) in N³⁻.

7 p, 10 e

Write the chemical formula for aluminum fluoride

AlF₃

Predict the chemical formula for the ionic compound formed by the elements Al and I

AlI₃

Determine the correct formula for aluminum oxide.

Al₂O₃

Write the chemical formula for barium nitride

Ba₃N₂

Write the chemical formula for carbon tetrafluoride

CF₄

Write the empirical formula corresponding to adenine, C₅H₅N₅.

CHN

Write the chemical formula for the carbonate ion

CO₃²⁻

Write the chemical formula for calcium sulfate dihydrate

CaSO₄•2H₂O

Predict the chemical formula for the ionic compound formed by Cu²⁺ and P³⁻

Cu₃P₂

Cathode rays are composed of what fundamental particle?

Electrons

Which scientist developed the nuclear model of the atom?

Ernest Rutherford

Columns on the periodic table are known as

Groups

Write the chemical formula for hydrobromic acid

HBr

Classify the following compounds as ionic or covalent: KCl, CrCl₃, Cl₂O.

Ionic, ionic, covalent.

Predict the chemical formula for the ionic compound formed by the elements K and S

K₂S

Which of the following is most likely to form a +2 ion?

Mg

Write the chemical formula for the ammonium ion

NH₄⁺

The nucleus of an atom contains:

Protons and neutrons

Which scientist determined the charge of the electron?

Robert Millikan

Of the following compounds, which contains a metalloid?

SiF₄

Which of the following represents a species with 16 protons and 18 electrons?

S²⁻

Consider two compounds. Compound A contains 15.7 g of sulfur and 18.6 g of fluorine. Compound B contains 25.4 g of sulfur and 60.2 g of fluorine. a. What is the mass ratio of fluorine to sulfur in Compound A? b. What is the mass ratio of fluorine to sulfur in Compound B? c. For Compound A, the ratio of fluorine to sulfur is 1.18. For Compound B, the ratio of fluorine to sulfur is 2.37. Using the Law of Definite Proportions (also called the Law of Constant Composition), could Compound A and Compound B be the same compound?

a. 18.6/15.7 = 1.18 b. 60.2/25.4 = 2.37 c. No, because they have different ratios of the same elements.

Provide the correct IUPAC name for Al(IO₃)₃.

aluminum iodate

Provide the correct IUPAC name for AlPO₄?

aluminum phosphate

Provide the correct IUPAC name for Ba(OH)₂.

barium hydroxide

Provide the correct IUPAC name for BaS.

barium sulfide

Provide the correct IUPAC name for BrCl₃.

bromine trichloride

Provide the correct IUPAC name for Ca(C₂H₃O₂)₂.

calcium acetate

Provide the correct IUPAC name for CaCO₃.

calcium carbonate

Provide the correct IUPAC name for CaCl₂ · 2H₂O.

calcium chloride dihydrate

Provide the correct IUPAC name for Ca(NO₃)₂?

calcium nitrate

Provide the correct IUPAC name for N₂O₄.

dinitrogen tetroxide

Provide the correct IUPAC name for HCN(aq).

hydrocyanic acid

Provide the correct IUPAC name for LiCl.

lithium chloride

Provide the correct IUPAC name for Mg₃P₂.

magnesium phosphide

Carbon dioxide is a _____ compound composed two types of _____ atoms.

molecular; nonmetal

Provide the correct IUPAC name for HNO₂(aq).

nitrous acid

Provide the correct IUPAC name for K₂SO₄?

potassium sulfate

An unknown element X has the following isotopes: ²⁵X (80.50% abundant, mass = 25.03 amu) and ²⁷X (19.50% abundant, mass = 26.98 amu). What is the average atomic mass of X in amu?

(0.8050 * 25.03) + (0.1950 * 26.98) = (20.15) + (5.261) = 25.41 amu

Determine the number of protons (p) and electrons (e) in Mg²⁺.

12 p, 10 e

There are two naturally occurring isotopes of europium, ¹⁵¹Eu (151.0 amu) and ¹⁵³Eu (153.0 amu). If the atomic mass of Eu is 151.96, what is the approximate natural abundance of ¹⁵¹Eu?

50%

Write the chemical formula for lead(II) nitrate

Pb(NO₃)₂

What element with a mass number of 100 has 56 neutrons in its nucleus?

Ruthenium (Ru)

Which is not one of Dalton's hypotheses of atomic theory?

The atoms of one element are the same as atoms of another element.

The Millikan oil drop experiment determined:

The charge of the electron

In two chemical reactions, 4.0 grams of oxygen combine with 3.0 grams of carbon to form one compound, and 8.0 grams of oxygen combine with 3 grams of carbon to form another. This can be explained by:

The law of multiple proportions

Which of the following pairs represent isotopes?

²⁸Si and ²⁹Si

Which of the following would be an isotope of ¹⁴N?

¹⁶N