General Chemistry Answers

How does the polarity of a substance affect the forces of attraction between the molecules?

Pb(NO₃)₂ + 2 NaI à PbI₂ + 2 NaNO₃                                  

1)     How many moles of lead (II) nitrate are needed to react completely with 10 moles of sodium iodide?

2)   How many moles of lead (II) iodide were produced when 5 moles of lead (II)nitrate were used in the reaction?

3)   If 100 grams of lead (II) nitrate were used in the reaction, how many grams of sodium iodide were used for a complete reaction?

4)   If 100 grams of lead (II) nitrate and 100 grams of sodium iodide were initially used in the reaction, which is the limiting reactant? Which is the excess reactant?

5)   Find the amount excess in grams in #4

6)   Suppose in the reaction in which 100 grams of lead(II) nitrate were all used up and only 100 grams of lead(II)iodide were obtained in the experiment, what is the percent yield?

7)   How many grams of the product were formed in no. 6 if the percent yield is 80%?

I want to vaporize or turn ethanol into a gas, to burn in a fire pit. I it take a propane bottle and pump air into the bottom and have a gas outlet at the top...will it be able to create enough gas to burn as the air moves through the liquid ethanol inside the tank?

What is the mole fraction HCI in an aqueous solution contains 44.2 grams of HCI and 88.6 grams of H2O?

1.   Molarity (M)

Calculate the molar concentration of a solution containing 13.4 g potassium hydroxide KOH in 355 mL of solution.

A biochemist who is studying the properties of certain sulfur S-containing compounds in the body wonders whether trace amounts of another nonmetallic elements might have similar behavior. To which element should she turn her attention?

(a)F (b)As (c)Se (d)Cr (e)p

Which two of these elements would you expect to show the greatest similarity in chemical and physical properties: B,Ca,He,Mg,P?

Using the spdf notation,write the electron configuration of iodine?

Write the equilibrium‑constant expression for the reaction shown in terms of [A],

 [B],

 [C],

 and [D].

A(g)+B(g)↽−

−⇀

2C(g)+D(g)

Note that 𝐾

c

,

 which is sometimes symbolized as 𝐾

 or 𝐾

eq

,

 denotes that the equilibrium constant is expressed using molar concentrations. For this question, 𝐾

c

 means the same thing as 𝐾

 and 𝐾

eq

.

Why is ethanol denser than isopropanol?

We are asked to compare its specific gravity using hydrometer. My readings are 0.820 SG for ethanol and 0.795 SG for isopropanol.