When each of these compounds dissolves in water, what ions are released and in what ratio? (a)

$$NaF$$

(b)

$$Li_3N$$

(c)

$$FeCI_3$$

(d)

$$K_2O$$

Element X has three electrons in its outermost orbit. Element Y has seven electrons in its outermost orbit (a) Classify each of these elements as metal or a non-metal. (b) What is the chemical formula of the ionic compound formed by these elements when they react together? (Use X and Y as the chemical symbols.)

Magnesium and chlorine react to form an ionic compound, (a) Which element Is the metal and which is the non-metal? (b) Draw a Bohr—Rutherford diagram (without neutrons) for each element. (c) How many electrons must the atoms of each element gain or lose to become a stable ion?

Silver reacts with sulfur to form a compound that has two silver Ions for every sulfide ion. Write the chemical formula for the compound.

(a) Draw the Bohr-Rutherford diagram (without neutrons) for an atom of each of the following elements: lithium, oxygen, calcium; and phosphorus. (b) Draw the; Bohr-Rutherford diagram (without neutrons) for the ion formed by each of the elements in (a). (c) Write the chemical symbol for each ion. (d) Name the noble gas with the same electron arrangement as each ion.

(a) Use the relative bond lengths of the C-C and C-O bonds to predict which of the following two equilibria lies farther to the right. (That is, predict which of the two compounds contains more of the conformation with the axial methyl group.) (b) Which one of the following compounds contains the greater amount of gauche conformation for internal rotation about the bond shown? Explain.

Which of the following ionic compounds is composed of only nonmetal atoms?

$$\mathrm{Al}_2\left(\mathrm{SO}_4\right)_3$$

Find the type, transform to normal form, and solve. Show your work in detail.

$$u_{xx}-4u_{xy}+5u_{yy}=0$$

Predict the empirical formulas of the ionic compounds formed from the following pairs of elements. Name each compound.

$\mathrm{Sr}$ and $\mathrm{F}$

Using clay (or glazing compounds), make a doughnut. Without puncturing or tearing the doughnut, reshape it into a topologically equivalent figure, a cut with a handle.

Antidifferentiate using the table of integrals. You may need to transform the integrand first.

$$\displaystyle \int \sin3\theta \cos5\theta\ d\theta$$

Predict whether each of the following compounds is soluble or insoluble in hexane, C$_{6}$H$_{14}$.

trichloroethylene, C$_{2}$HCl$_{3}$

Give the formula and the number of each ion that makes up each of the following compounds:\

$$\mathrm{NaCH}_3 \mathrm{CO}_2$$

Use linearity and Table of the Laplace transforms to determine the Laplace transform of the function $f(t)=3+t+e^{-t} \sin 2 t$.