Choose the shape (1-6) that matches each of the following descriptions (a-c):

1. linear
2. bent $\left(109^{\circ}\right)$
3. trigonal planar
4. bent $\left(120^{\circ}\right)$ 5. trigonal pyramidal
5. tetrahedral a. a molecule with a central atom that has four electron groups and two bonded atoms b. a molecule with a central atom that has two electron groups and two bonded atoms c. a molecule with a central atom that has three electron groups and two bonded atoms

Choose the shape (1 to 6) that matches the description: a molecule with a central atom that has three electron groups and two bonded atoms

1. linear
2. bent (109$\degree$)
3. trigonal planar
4. bent (120$\degree$)
5. trigonal pyramidal
6. tetrahedral

Choose the shape (1 to 6) that matches each of the following descriptions (a to c): l. linear 2. bent ($109\degree$) 3. trigonal planar 4. bent ($120\degree$) 5. trigonal pyramidal 6. tetrahedral a molecule with a central atom that has three electron groups and two bonded atoms

What is the shape of a molecule with a central atom that has four electron groups and two bonded atoms?

Using the periodic table, arrange the atoms in each of the following sets in order of increasing electronegativity: a. $\mathrm{Li}, \mathrm{Na}, \mathrm{K}$ b. $\mathrm{Na}, \mathrm{Cl}, \mathrm{P}$ c. $\mathrm{Se}, \mathrm{Ca}, \mathrm{O}$

When is it necessary to draw a multiple bond in a Lewis structure?

Name each of the following ionic compounds: $Zn({C_2H_3 O_2)}_2$, cold remedy

Choose the shape (1-6) that matches each of the following descriptions (a-c):

1. linear $\quad$ 2. bent $\left(109^{\circ}\right) \quad$ 3. trigonal planar
2. bent $\left(120^{\circ}\right)$ 5. trigonal pyramidal
3. tetrahedral a. a molecule with a central atom that has four electron groups and four bonded atoms b. a molecule with a central atom that has four electron groups and three bonded atoms c. a molecule with a central atom that has three electron groups and three bonded atoms

Draw resonance structures for each of the following molecules or ions: a. $\mathrm{HCO}_2^{-}(\mathrm{C}$ is the central atom $)$ b. $\mathrm{N}_2 \mathrm{O}$

A 3.0-kg block of lead is taken from a furnace at $300^{\circ} \mathrm{C}$ and placed on a large block of ice at $0{ }^{\circ} \mathrm{C}$. The specific heat of lead is $0.13 \mathrm{~J} / \mathrm{g}{ }^{\circ} \mathrm{C}$. If all the heat given up by the lead is used to melt ice, how much ice is melted when the temperature of the lead drops to $0{ }^{\circ} \mathrm{C}$ ? $(10.5)$

Draw resonance structures for each of the following molecules or ions: a. $\mathrm{ClNO}_2$ ( $\mathrm{N}$ is the central atom) b. $\mathrm{OCN}^{-}(\mathrm{C}$ is the central atom)

Suggest an explanation for the observation that the heat of fusion of a substance is always smaller than its heat of vaporization.

An ice cube at $0^{\circ} \mathrm{C}$ with a mass of $115 \mathrm{~g}$ is added to $\mathrm{H}_2 \mathrm{O}$ in a beaker that has a temperature of $64.0^{\circ} \mathrm{C}$. If the final temperature of the mixture is $24.0^{\circ} \mathrm{C}$, what was the initial mass of the warm water? (10.5)

An ice cube tray holds $325 \mathrm{~g}$ of water. If the water initially has a temperature of $25^{\circ} \mathrm{C}$, how many kilojoules of heat must be removed to cool and freeze the water at $0^{\circ} \mathrm{C} ?(10.5)$