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When measuring volumes, when should you use a beaker and when should you use a graduated cylinder?

What is the oxidation number for H2O?

Determine the electron-domain geometry and molecular geometry for each of the following: a. SBr₂ b. PI₄⁺ c. IBr₂⁻ The following three compounds all have the same general formula, XF₄. Compare the electron-domain geometries of these three compounds and explain what characteristic(s) of the central atom causes differences in geometry. a. SiF₄ b. SeF₄ c. XeF₄

The electron domain and molecular geometry of SO3 are: octahedral, seesaw trigonal bipyramidal, trigonal planar trigonal planar, trigonal planar trigonal planar, bent

Identify each element as a metal, metalloid, or nonmetal. Fluorine: Nonmetal Germanium: Metalloid Zinc: Metal Phosphorus: Nonmetal Lithium: Metal

The molar mass of KCl is 74.55 g/mol. If 8.45 g of KCl are dissolved in 0.750 L of solution, what is the molarity of the solution? A. 0.113 M B. 0.151 M C. 6.62 M D. 11.3 M

What is the molecular geometry, or shape, of phosphorus trichloride (PCl3 )?

Bent Molecular Geometry (Tetrahedral Electron Geometry) is observed in molecules where: A. There are three bonded atoms and no lone pairs. B. There are three bonded atoms and one lone pair. C. There are four bonded atoms and two lone pairs. D. There are five bonded atoms in a trigonal bipyramidal arrangement.

Is BeCl2 polar or nonpolar?

What is a combustion reaction? A. A reaction between a molecule and oxygen that produces heat B. A reaction between a molecule and carbon dioxide that produces oxygen C. A reaction between hydrogen and carbon that forms a hydrocarbon D. A reaction between water and oxygen that produces water vapor

What are the expected bond angles in ICl 4+? Select all that apply: A. 90 degrees B. 109.5 degrees C. 180 degrees D. 120 degrees

Which layer is aqueous and which is organic (bottom or top)? Will the result be the same if dichloromethane (DCM) is used as the organic solvent? Explain.

The molar mass of LiF is 25.94 g/mol. How many moles of LiF are present in 10.37 g?

What happens to the intensity of the solution's color as the concentration of the solute changes? A. The intensity of the color directly changes in response to the concentration. B. The intensity of the color inversely changes in response to the concentration. C. The intensity of the color always increases in response to any concentration change. D. The intensity of the color always decreases in response to any concentration change. E. The intensity of the color does not change in response to any concentration change.

Is Cl2 polar or nonpolar?

Draw the Lewis structure for CHO2- on a piece of paper. Note: CHO2- has resonance structures, and there are two forms of the drawn ion. Draw both structures. Please draw a clear picture so it can be understood better.

Is carbon a metal, nonmetal, or semi-metal?

Draw the Lewis dot diagram for a neutral atom of Br.

What is the total number of valence electrons in a water molecule?

Check your ability to correctly define some of the terms associated with redox reactions. (a) A chemical species that gets reduced during a chemical reaction: loses electrons or gains electrons? (b) A chemical species that gets reduced during a chemical reaction: changes to a more negative oxidation state or changes to a more positive oxidation state? (c) A chemical species that gets reduced during a chemical reaction: is a reducing agent or is an oxidizing agent? (d) A chemical species that gets reduced during a chemical reaction: has a high-energy filled orbital or has a low-energy unfilled orbital? (e) A chemical species that gets reduced during a chemical reaction: obtains electrons from a reducing agent or obtains electrons from an oxidizing agent?

Enter the molecular formula for butane, C4 H10. Express in a chemical formula.

Calculate the density of potassium.

Draw the Lewis structure for the conjugate acid of ammonia. Draw the Lewis structure for the conjugate base of ammonia.

Calculate the molar mass of NH4NO2.

How many moles of Mg are in MgO?

Find silver (Ag) on the periodic table. What are the block and period associated with it?

Construct a Lewis structure for hydrogen peroxide, H2O2, in which each atom achieves a stable noble-gas electron configuration. Draw the molecule by placing atoms on the grid and connecting them with bonds. Include all lone pairs of electrons.

Determine the electron geometry, molecular geometry, and polarity of N2O (O central). A. eg = linear, mg = linear, nonpolar B. eg = tetrahedral, mg = linear, nonpolar C. eg = tetrahedral, mg = bent, polar D. eg = linear, mg = linear, polar

How many valence electrons does an atom of rubidium (Rb, atomic number 37) have? A. One B. Five C. Six D. 37

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.