Which of the following represents a polar covalent bond

Alecsey [184]

a) When the reaction takes place a yellow precipitate will be formed.

b) The law of conservation of mass is true.

<u>Explanation:</u>

a) When a lead nitrate solution is mixed with a potassium chromate solution, a yellow precipitate containing lead forms according to the equation:

$Pb(NO_3)_2 (aq) + K_2CrO_4 (aq)$ → $2 KNO_3 (aq) + PbCrO_4(s).$

b) Law of conservation of mass for the given reaction is true.

From the given table we know the mass of reactants and its products.

Law of conservation of mass is a principle when a reaction takes place in a closed system, the mass of the products and reactants in the system doesn't change.

⇒The sum of the mass of the reactants = The sum of the mass of the products.

The sum of the reactants = 128.71+128.97.

= 257.68 g.

The sum of the products = 154.10+103.58.

= 257.68 g.

Thus law of conservation of mass is true for the above reaction.

3 0

3 years ago

HOW MANY M ARE IN 3.0X105 MM?

erik [133]

The answer to the question is 300meters.

7 0

3 years ago

A 7.0 g sample of a hydrocarbon (a molecule that has only hydrogen and carbon) is subject to combustion analysis. The mass of CO

Akimi4 [234]

Answer: The empirical formula for the given compound is $CH_2$

Explanation:

The chemical equation for the combustion of compound having carbon and hydrogen follows:

$C_xH_y+O_2\rightarrow CO_2+H_2O$

where, 'x' and 'y' are the subscripts of carbon and hydrogen respectively.

We are given:

Mass of $CO_2=22.0g$

We know that:

Molar mass of carbon dioxide = 44 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 22.0 g of carbon dioxide, $\frac{12}{44}\times 22.0=6g$ of carbon will be contained.

For calculating the mass of hydrogen:

Mass of hydrogen = Mass of sample - Mass of carbon

Mass of hydrogen = 7.0 g - 6 g

Mass of hydrogen = 1.0 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{6g}{12g/mole}=0.5moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{1.0g}{1g/mole}=1.0moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.5 moles.

For Carbon = $\frac{0.5}{0.5}=1$

For Hydrogen = $\frac{1.0}{0.5}=2$

Step 3: Taking the mole ratio as their subscripts.

The ratio of Fe : C : H = 1 : 2

Hence, the empirical formula for the given compound is $C_{1}H_{2}=CH_2$

4 0

4 years ago

Which compound contains both covalent and ionic bonds? <br> a. NCl3 b. NaF c. HCN d. NH4OH

Marina86 [1]

<h2> $NH_4OH$ contains both covalent and ionic bonds.</h2>

Explanation:

A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals.

An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element or the metal and the element which accepts the electrons is known as electronegative element or non metal.

a. $NCl_3$ contain covalent bonds as they are made up of non metals only.

b. $NaF$ contain ionic bonds as they are made up of sodium metal and fluorine non metal.

c. $HCN$ contain covalent bonds as they are made up of non metals only.

d. $NH_4OH$ contain ionic bonds between $NH_4$ and $OH$ and covalent between N and H in $NH_4^+$

Learn more about ionic and covalent bonds

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brainly.com/question/2877158

8 0

3 years ago

Where on earth did people decide they wanted to go many years ago

adell [148]

Answer:

Many years ago, people living on the Earth, desired to go to the outer space.

Explanation:

When man initiate to go outer space:

Many times ago, people used to think about the world out of Earth, the space and the sky. These thoughts generated the idea of thinking and imagining the space and the moon.

The idea turned into a movie by Georges Méliès, which was inspired by a book written by Jules Verne. The movie gave the idea to Konstantin Tsiolkovsky, a Russian man to develop many ideas which were implemented by Russia and America to build airplanes and rockets that we see launching at present.

A small though became an idea which gave birth to a new invention through which people live their dreams of going in the outer space. Incredible!

3 0

3 years ago