All of the following are conductors of electricity except

I need help with my homework.Calculate the number of formula units in: 41.5 grams CaBr2

lana66690 [7]

Answer:

$\text{ }1.25\times10^{23}\text{ formula units}$

Explanation:

Here, we want to calculate the number of formula units in the given molecule

We start by getting the number of moles

To get the number of moles, we have to divide the mass given by the molar mass

The molar mass is the mass per mole

The molar mass of calcium bromide is 200 g/mol

Thus, we have the number of moles as follows:

$\frac{41.5}{200}\text{ = 0.2075 mol}$

The number of formula units in a mole is:

$1\text{ mole = 6.02 }\times10^{22}\text{ formula units}$

The number of formula units in 0.2075 mole will be:

$0.2075\text{ }\times6.02\times10^{23}\text{ = }1.25\times10^{23}\text{ formula units}$

5 0

1 year ago

Examine the ph scale below. How does household bleach compare to household ammonia?

Kazeer [188]

Answer is: household ammonia has 10 times higher H⁺ concentration.

1) pH(household ammonia) = 11.5.

pH = -log[H⁺], approximately the negative of the base 10 logarithm of the molar concentration of hydrogen ions.

[H⁺] = 10∧(-pH).

[H⁺] = 10∧(-11.5).

[H⁺] = 3.16·10⁻¹² M; concentration of hydrogen ions.

2) pH(household bleach) = 12.5.

[H⁺] = 10∧(-12.5).

[H⁺] = 3.16·10⁻¹³ M.

3) 3.16·10⁻¹² M / 3.16·10⁻¹³ M = 10.

6 0

3 years ago

Read 2 more answers

In a compound, such as CH3OH, how determine which is the central atom?

svetlana [45]

Answer:

Choose the least electronegative atom other than H.

Explanation:

A Lewis structure consists of terminal atoms and one or more central atoms.

H can be only a terminal atom because it can form only one bond.

So the central atom must be either C or O.

The central atom is the less electronegative atom: C.

So, start the Lewis structure with a central C atom.

Then attach an O atom to get C-O.

Finally, attach the H atoms.

The condensed formula often gives you a clue where they go.

The formula CH₃OH implies that there are 3 H atoms on C and one on O.

The connectivity of the atoms is then as in the diagram below.

3 0

3 years ago

Aqueous sulfuric acid (H2SO4) reacts with solid sodium hydroxide (NaOH) to produce aqeous sodium sulfate (Na2SO4) and liquid wat

Montano1993 [528]

Answer:

The theoretical yield of water formed is 2.2 grams

Explanation:

Step 1: Data given

Mass of H2SO4 = 5.9 grams

Mass of NaOH = 6.6 grams

Molar mass H2SO4 = 98.08 g/mol

Molar mass of NaOH = 40.0 g/mol

Step 2: The balanced equation

2NaOH + H2SO4 → Na2SO4 + 2H2O

Step 3: Calculate moles

Moles = mass / molar mass

Moles H2SO4 = 5.9 grams / 98.08 g/mol

Moles H2SO4 = 0.060 moles

Moles NaOH = 6.6 grams / 40.0 g/mol

Moles NaOH = 0.165 moles

Step 4: Calculate the limiting reactant

For 2 moles NaOH we need 1 mol H2SO4 to produce 1 mol Na2SO4 and 2 moles H2O

H2SO4 is the limiting reactant. It will completely be consumed ( 0.060 moles). NaOH is in excess . There will react 2*0.060 = 0.120 moles

There will remain 0.165 - 0.120 = 0.045 moles NaOH

Step 5: Calculate moles H2O

For 2 moles NaOH we need 1 mol H2SO4 to produce 1 mol Na2SO4 and 2 moles H2O

For 0.0600 moles H2SO4 we'll have 2*0.0600 = 0.120 moles H2O

Step 6: Calculate mass H2O

Mass H2O = 0.120 moles * 18.02 g/mol

Mass H2O = 2.16 grams

The theoretical yield of water formed is 2.2 grams

4 0

3 years ago

How many grams of sodium are needed to produce 12.5 g of sodium oxide

lutik1710 [3]

1. (b) I hope this helps!

7 0

3 years ago