How many moles are present when there are 1.00.1026 molecules of water?

Group-8 elements are inert and possess

Artemon [7]

Answer:

Group 8 elements are inert and possess :

1. Low Boiling Points

2. High ionization energies

3. Electronegativities is very low

4. No color, odor

Explanation:

Group 8 elements are also called as Noble Gases. They are unreactive.

They have low boiling points means they remains monoatomic at room temperature. Having high ionization energy means that it is very difficult to remove an electron from its valence shell.

3 0

4 years ago

What is the molarity of an aqueous solution that contains 78g of C6H12O6 dissolved in 2500 mL of solution?

dusya [7]

Answer:

$\boxed {\boxed {\sf molarity = 0.17 \ M \ C_6H_12O_6}}$

Explanation:

Molarity is found by dividing the moles of solute by liters of solution.

$molarity = \frac {moles}{liters}$

We are given grams of a compound and milliliters of solution, so we must make 2 conversions.

1. Gram to Moles

We must use the molar mass. First, use the Periodic Table to find the molar masses of the individual elements.

C: 12.011 g/mol
H: 1.008 g/mol
O: 15.999 g/mol

Next, look at the formula and note the subscripts. This tells us the number of atoms in 1 molecule. We multiply the molar mass of each element by its subscript.

6(12.011)+12(1.008)+6(15.999)=180.156 g/mol

Use this number as a ratio.

$\frac {180.156 \ g\ C_6H_12 O_6}{ 1 \ mol \ C_6H_12O_6}$

Multiply by the given number of grams.

$78 \ g \ C_6H_12O_6 *\frac {180.156 \ g\ C_6H_12 O_6}{ 1 \ mol \ C_6H_12O_6}$

Flip the fraction and divide.

$78 \ g \ C_6H_12O_6 *\frac { 1 \ mol \ C_6H_12O_6}{180.156 \ g\ C_6H_12 O_6}$

$\frac { 78 \ mol \ C_6H_12O_6}{180.156 }= 0.432958102977 \ mol \ C_6H_12O_6$

2. Milliliters to Liters

There are 1000 milliliters in 1 liter.

$\frac {1 \ L }{ 1000 \ mL}$

Multiply by 2500 mL.

$2500 \ mL* \frac {1 \ L }{ 1000 \ mL}$

$2500 * \frac {1 \ L }{ 1000 }= 2.5 \ L$

3. Calculate Molarity

Finally, divide the moles by the liters.

$molarity = \frac {0.432958102977 \ mol \ C_6H_12O_6}{ 2.5 \ L}$

$molarity = 0.173183241191 \ mol \ C_6H_12O_6/L$

The original measurement has 2 significant figures, so our answer must have the same. That is the hundredth place and the 3 tells us to leave the 7.

$molarity \approx 0.17 \ mol \ C_6H_12O_6 /L$

1 mole per liter is also equal to 1 M.

$molarity = 0.17 \ M \ C_6H_12O_6$

3 0

3 years ago

Covalent bonds involve the sharing of?

4vir4ik [10]

Answer:

A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.

Explanation:

I hope this helps

7 0

3 years ago

How many grams of iron can be made with 21.5g of Fe2O3

SIZIF [17.4K]

The mass (in grams) of iron, Fe that can be made from 21.5 g of Fe₂O₃ is 15.04 g

We'll begin by writing the balanced equation for the reaction. This is given below:

2Fe₂O₃ -> 4Fe + 3O₂

Molar mass of Fe₂O₃ = 159.7 g/mol
Mass of Fe₂O₃ from the balanced equation = 2 × 159.7 = 319.4 g
Molar mass of Fe = 55.85 g/mol
Mass of Fe from the balanced equation = 4 × 55.85 = 223.4 g

From the balanced equation above,

319.4 g of Fe₂O₃ decomposed to produce 223.4 g of Fe

<h3>How to determine the mass of iron, Fe produced</h3>

From the balanced equation above,

319.4 g of Fe₂O₃ decomposed to produce 223.4 g of Fe

Therefore,

21.5 g of Fe₂O₃ will decompose to produce = (21.5 × 223.4) / 319.4 = 15.04 g of Fe

Thus, 15.04 g of Fe were produced.

Learn more about stoichiometry:

brainly.com/question/9526265

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5 0

1 year ago

In the process of attempting to characterize a substance, a chemist makes the following observations: (a) The substance is a sil

Amiraneli [1.4K]

The question is incomplete, this is the complete question;

In the process of attempting to characterize a substance, a chemist makes the following observations. Which are physical properties and which are chemical properties?

(a) The substance is a silvery white, lustrous metal.

(b) The substance melts at 649 ∘C

(c) The substance boils at 1105 ∘C.

(d) The density of the substance at 20 ∘C is 1.738 g/cm³.

(e) The substance burns in air, producing an intense white light.

(f) The substance reacts with chlorine to give a brittle white solid.

(g) The substance can be pounded into thin sheets or drawn into wires.

(h) The substance is a good conductor of electricity.

Answer:

(a) Physical

(b) Physical

(c) Physical

(d) Physical

(e) Chemical

(f) Chemical

(g) Physical

(h) Physical

Explanation:

(a) The substance is a silvery white, lustrous metal - is appearance which is physical.

(b) The substance melts at 649 ∘C metling point is a physical measurement

(c) The substance boils at 1105 ∘C boiling point is a physical measurement

(d) The density of the substance at 20 ∘C is 1.738 g/cm3 how heavy a substance is,is physical.

(e) The substance burns in air, producing an intense white light. Burning is a chemical change. It is a reaction of a substance with oxygen

(f) The substance reacts with chlorine to give a brittle white solid. This is a chemical reaction as the question says.

(g) The substance can be pounded into thin sheets or drawn into wires. Ductility is a physical change, the substance remains chemically unchanged

(h) The substance is a good conductor of electricity. Any conductivity is physical, the substance remains chemically unchanged

7 0

3 years ago