Can an element with eight valence electrons still be reactive?

An object has a mass of 45.0 g and a volume of 4.0 ml. what is its density?

andreev551 [17]

Answer:

The answer is

Explanation:

The density of a substance can be found by using the formula

$Density = \frac{mass}{volume}$

From the question

mass = 45 g

volume = 4 mL

Substitute the values into the above formula and solve for the density

We have

$Density = \frac{45}{4}$

We have the final answer as

Hope this helps you

4 0

3 years ago

How many atoms of carbon are combined to with 2.81 moles of hydrogen atoms in a sample of the compound ethane, C2H6?

puteri [66]

Answer:

5.64×10²³ atoms C

Explanation:

Convert moles of H to moles of C:

2.81 mol H × (2 mol C / 6 mol H) = 0.937 mol C

Convert moles of C to atoms of C:

0.937 mol C × (6.02×10²³ atoms C / mol C) = 5.64×10²³ atoms C

5 0

3 years ago

Place the following covalent bonds in order from least to most polar: a. H-Cl b. H-Br c. H-S d. H-C

timofeeve [1]

Answer:

The Order is as follow,

C-H < S-H < H-Br < H-Cl

Explanation:

Polarity depends on the electronegativity difference between two atoms, greater the electronegativity difference, greater will be the polarity of bond and vice versa.

Electronegativity Difference between Hydrogen and other given elements are as follow,

1) C-H;

E.N of Carbon = 2.55

E.N of Hydrogen = 2.20

------------

Difference 0.35

2) S-H;

E.N of Sulfur = 2.58

E.N of Hydrogen = 2.20

------------

Difference 0.38

3) H-Br;

E.N of Bromine = 2.96

E.N of Hydrogen = 2.20

-------------

Difference 0.76

4) H-Cl;

E.N of Chlorine = 3.16

E.N of Hydrogen = 2.20

-----------

Difference 0.96

Hence it is proved that the greatest electronegativity difference is found between H and Chlorine in H-Cl, therefore it is highly polar bond and vice versa.

7 0

3 years ago

Which of the following is a testable hypothesis?

Sonja [21]

The answer would be B because you can go and find evidence and facts to conduct an investigation on that.

6 0

3 years ago

Read 2 more answers

Dihydrogen dioxide decomposes into water and oxygen gas. Calculate the amounts requested if 1.34 moles of dihydrogen dioxide rea

a_sh-v [17]

Answers:

a. Moles of oxygen formed: 0.670 mol

b. Moles of water formed: 1.34 mol

c. Mass of water formed: 24.1 g

d. Mass of oxygen formed: 21.4 g

Explanation:

Dihdyrogen dioxide is the chemical name for a compound made of two hydrogen atoms and two oxide atoms, i.e. H₂O₂, which is also known as hydrogen peroxide or oxygenated water.

The decomposition reaction of dihydrogen dioxide into water and oxygen gas is represented by the balanced chemical equation:

$2H_2O_2(l)\rightarrow 2H_2O(l)+O_2(g)$

The mole ratios derived from that balanced chemical equation are:

2 mol H₂O₂ : 2 mol H₂O : 1 mol O₂

a. Moles of oxygen formed

Set the proportion using the theoretical mole ratio of H₂O₂ to O₂ and the amount of moles of dyhydrogen dioxide that react:

$2\text{ mol }H_2O_2/1\text{ mol }O_2=1.34\text{ mol }H_2O_2/x$

When you solve for x, you get:

x = 1.34 mol H₂O₂ × 1 mol O₂ / 2 mol H₂O₂ = 0.670 mol O₂

b. Moles of water formed

Set the proportion using the theoretical mole ratio of H₂O₂ to H₂O and the amount of moles of dyhydrogen dioxide that react:

$2\text{ mol }H_2O_2/2\text{ mol }H_2O=1.34\text{ mol }H_2O_2/x$

When you solve for x, you get:

x = 1.34 mol H₂O₂ × 2 mol H₂O / 2 mol H₂O₂ = 1.34 mol H₂O

c. Mass of water formed

Using the number of moles of water calculated in the part b., you calculate the mass of water formed, in grams, using the molar mass of water:

Molar mass of water = 18.015 g/mol

Number of moles = mass in grams / molar mass

⇒ mass in grams = number of moles × molar mass

⇒ mass in grams = 1.34 mol × 18.015 g/mol = 24.1 g

d. Mass of oxygen formed

Using the number of moles of oxygen determined in the part a., you calculate the mass in grams using the molar mass of O₂.

Molar mass of O₂ = 32.00 g/mol

mass = molar mass × number of moles

mass = 32.00 g/mol × 0.670 mol = 21.4 g.

5 0

3 years ago