Iron(III) sulfide is an ionic compound. Therefore:

Slides:

Advertisements

Similar presentations

The term valence refers to the outermost shell.

Advertisements

QUESTION: A 25.0 gram sample of a compound is found to be 24% chlorine by mass. What is the percentage of chlorine in a 50.0 g sample of the compound?

Bohr assumed electrons move around the nucleus in circular orbits.

QUESTION: Which of the following elements is a post-transition metal? A. silicon, B. lead, C. sodium, D. chromium SCRIPT: Which of the following.

How to tell from the formula if a compound is ionic:

FeSO4 is an ionic compound. Cation is iron(?). Need to figure out “?”

QUESTION: Which of the following elements is a transition metal? A. silicon, B. lead, C. sodium, D. chromium SCRIPT: Which of the following elements.

How to tell from the name if a compound is ionic:

SO3: one Sulfur atom: 16 protons

Uncertainty of g: tenths place

CuCl2 is an ionic compound.

C. molybdate, MoO42-, D. permanganate, MnO4-

Which of these is the formula of a reactant in this reaction?

Smallest set is obtained if greatest common factor is 1

QUESTION: Which of the following describes a cation? A. an aluminum ion (Al3+), B. an oxygen atom that has gained 2 electrons C. an ion with 17 protons.

Therefore the correct answer is D.

Ions are formed by loss or gain of electrons.

How many cations are in 2.00 mol Na3PO4?

QUESTION: Which of the following describes an anion? A. a sodium ion (Na+), B. a calcium ion that has lost 2 electrons C. an ion with 8 protons and 10.

PCl5 is a binary, molecular compound. Binary: two elements (P and Cl)

QUESTION: Which of the following is a metalloid? A. Potassium, B. Silicon, C. Iron, D. Helium SCRIPT: Which of the following is a metalloid? A.

In nature, substances are typically mixed.

Mass of proton or neutron: 1.0 u Mass of electron: u

Trends in atomic size: opposite of trend in ionization energy

CLICK Here are some possible molecular formulas When x=1, we have NO2.

QUESTION: Which of the following elements is the best electrical conductor? A. carbon, B. germanium, C. manganese, D. iodine SCRIPT: A. carbon,

Ions are formed by loss or gain of electrons.

Ammonium sulfide is an ionic compound. Cation is ammonium ion. NH4+

QUESTION: Which of the following elements is a metal that belongs to a main group or representative group? A. magnesium, B. zinc, C. sulfur, D.

A. 0.8 g/mL, B g/mL, C g/mL, D. 1.3 g/mL

Since both carbon and oxygen are nonmetals, choice C is wrong.

One Ca2+ ion: +2 One CO32- ion: -2

There are 3 orbitals in a p subshell (ml = -1, 0, or +1).

Ions are formed by loss or gain of electrons.

QUESTION: Which type of element has the lowest electronegativity? A. a metal, B. a nonmetal, C. a metalloid Electronegativity is a measure of the.

Mathematically, this implies that the ratio of the amount of element

QUESTION: What is the electron configuration of Fe3+? A. [Ar] 4s2 3d6 B. [Ar] 4s2 3d3 C. [Ar] 4s1 3d4 D. [Ar] 3d5 SCRIPT: What is the electron configuration.

How many neutrons does an O-18 atom have? A. 8, B. 10, C. 16, D. 18

One Na+ ion: +1 One CO32- ion: -2

Dinitrogen tetroxide is a binary, molecular compound.

A. Mg(s) + N2(g)  MgN2(s), B. Mg(s) + O2(g)  MgO2(s)

QUESTION: How should the result of the following calculation be reported, assuming that 1.8 and 32 are exact numbers? 32 + (1.8)(2.37) A. 36,

Cobalt(II) chloride is an ionic compound. Therefore:

What is the Kelvin temperature equivalent to 50.00oF?

The oxygen-to-carbon ratio in that sample is x over 36.0 HIGHLIGHT

What is the Kelvin temperature equivalent to 25.00oC?

The simplest collection of ions with a total charge of zero would be….

Each calcium ion has a charge of +2,

Na2S is a binary, ionic compound. Binary: two elements (Na and S)

Choice A is obviously a correct formula --- it has four hydrogen atoms

Chloride: Cl-, monatomic, not an oxoanion

Allowed values of principal quantum number (n): positive integers

Which figure below best represents an aqueous solution of CaCl2?

Oxoanions have names ending in “ate” or “ite”

Therefore, the correct answer is A.

Iron(III) sulfate is an ionic compound. Cation is iron(III) ion. Fe3+

Mercury(I) or mercurous ion is Hg22+.

QUESTION: A sample of matter is heated and found to start melting at 75.0oC. While melting, the sample temperature continues to rise to about 85.0oC.

Ions are formed by loss or gain of electrons.

CLICK PAUSE END RECORDING

QUESTION: What is the maximum number of of electrons that can be assigned to a 2p orbital of an atom? A. 2, B. 3, C. 6, D. 10 Pauli’s Exclusion.

A. an element and two compounds, B. two elements and a compound,

Here’s a general strategy for determining empirical formulas.

Sodium phosphate is an ionic compound. Cation is sodium ion. Na+

0.800 m has three significant digits

What do molecules and polyatomic ions have in common?

Potassium hydrogen phosphate is an ionic compound.

80.00 g has four significant digits

C. CaCl2(s)  Ca2+(aq) + Cl22-(aq)

K2CO3 is an ionic compound. Cation is potassium ion: K+

Presentation transcript:

Iron(III) sulfide is an ionic compound. Therefore: QUESTION: Which of the following is the formula for iron(III) sulfide? A. FeS, B. Fe3S, C. Fe2S3, D. Fe3S2 Iron(III) sulfide is an ionic compound. Therefore: Cation is iron(III), or Fe3+ Anion is sulfide, or S2- Formula unit, the simplest combination of ions with a total charge of zero, consists of two cations and three anions. 2 x (+3) = +6 3 x (-2) = -6 Cations: +3, +3, +3, +3, +3, … Anions: -2, -2, -2, -2, -2, … SCRIPT: Which of the following is the formula for iron(III) sulfide? A. FeS, B. Fe3S, C. Fe2S3, D. Fe3S2 PAUSE To name a compound given its formula, we need to first classify the compound, then apply the rule for that type of compound. CLICK Iron three sulfide is an ionic compound…. We know it’s ionic because iron is a metallic element. In an ionic compound, the cation is named first. Therefore…. the cation is iron three. The roman numeral three tells us that the charge of the cation is +3. HIGHLIGHT …. The anion is sulfide. By referring to a periodic table, we find that sulfur belongs to group six A. By now, you should know that members of this group form monatomic ions with a charge of –2. Sulfide is S with a –2 charge. To write the formula for an ionic compound, we determine the simplest combination of ions with a total charge of zero. In this case, the simplest combination consists of two cations and three anions. Two iron three cations… will have a total charge of +6. Two times +3 is +6. … and three sulfide ions… will have have a total charge of –6. Three times –2 is –6. Therefore, the formula should have subscripts to tell us that… in one formula unit… CLICK CLICK There are two cations… And three anions…. The correct answer is C. Note that we do not indicate the charges of the ions in the formula of a compound. CLICK PAUSE END RECORDING

Video ID: 1-26-5 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Narrator: Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08