Chemistryacademic

What do all of the elements in a given horizontal row of the periodic table have in common?

How many total electrons can the d orbitals hold? A. 3 B. 10 C. 2

According to its periodic table entry, how many electrons does nickel have in its valence level? A. 2 B. 8 C. 16 D. 28

The empirical formula of the compound containing 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass is _____. A. C₆H₁₂O₆ B. C₃H₆O₃ C. C₂H₇O₃ D. CHO E. CH₂O

Is HF polar or nonpolar?

Which statement best describes why a water molecule is polar? A. Oxygen exerts a stronger pull on the shared electrons than the hydrogens do. B. There are two hydrogen atoms, but only one oxygen atom. C. Electrons are always shared equally. D. Oxygen is bigger than hydrogen, giving it a stronger positive charge.

What is the charge of a fluorine (F) ion? A. -7 B. -1 C. +1 D. +7

According to the VSEPR model, the predicted molecular geometry of ammonia, NH₃, is: linear trigonal planar tetrahedral trigonal pyramidal

Use VSEPR theory to predict the molecular geometry (shape) of nitrogen trichloride, NCl₃. A. Linear B. Trigonal planar C. Bent D. Tetrahedral E. Trigonal pyramidal

How many protons, neutrons, and electrons are in selenium?

CH3F is a polar molecule, even though the tetrahedral geometry often leads to nonpolar molecules. Explain.

K is the abbreviation for calcium. A. True B. False

How can you tell if a chemical equation represents hydrolysis?

What would the charge be on an ion of selenium (Se)?

Which of the following atoms is diamagnetic in the ground electronic state? A. S B. Mn C. I D. Sr

What is the formula for nitrogen trihydride?

An atom of titanium has an atomic number of 22 and a mass number of 49. Calculate the number of protons and neutrons in this atom. If the atom of titanium is neutral, how many electrons are in the atom?

What type of bond exists between hydrogen and chlorine in HCl (hydrochloric acid)? How do you know this?

What is the molar mass of KClO₃?

What is the electron configuration for bismuth (Bi)?

Is buttermilk an example of a homogeneous or heterogeneous mixture?

Is fluorine a metal or a nonmetal? How many valence electrons does a fluorine atom have?

Which of the following is the Lewis dot structure for Silicon (Si)? A. Si B. Si:

How many valence electrons are there in the valence shell of sodium, Na (atomic number 11)? A. three B. one C. two D. four

Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have? A. 19 B. 58 C. 20 D. 39

What is the process to convert moles into grams?

Which type of bond has an electronegativity difference greater than 1.7? A. ionic B. metallic C. nonpolar covalent D. polar covalent

The radius of an atom of gold (Au) is about 1.35 Å (angstrom). a. Express this distance in nanometers (nm) and in picometers (pm). b. How many gold atoms would have to be lined up to span 1.0 mm? c. If the atom is assumed to be a sphere, what is the volume in cm3 of a single Au atom?

Write the formula for the following covalent compound: phosphorus triiodide.

We recognize acids when we see a(n) ______ with an anion. The name of the acid is derived from the name of its ______. An ate anion, like nitrate, forms an acid named ______. Sulfurous acid (H2SO3) is formed from a ______ ion. a. Positive ion b. Negative ion c. Neutral ion d. Not mentioned