All categories

4 years ago

Simple question. How many groups and how many periods are on the periodic table? Which directions do they go?

Chemistry

2 answers:

stepan [7]4 years ago

5 0

There is 18 groups in the periodic table.. periodic tables go from left to right. hope that helped

zhuklara [117]4 years ago

5 0

Hey there,
There are 18 groups also known as vertical columns in a periodic table. Groups are vertical and Columns are horizontal

Hope this helps ^_^

~Top

You might be interested in

Indicate the types of forces that are involved between the solute and solvent when forming a homogeneous solution between ch3ch2

Bess [88]

Answer:
Dispersion Forces are found between n-Pentane (CH₃-CH₂-CH₂-CH₂-CH₃) and n-Hexane (CH₃-CH₂-CH₂-CH₂-CH₂-CH₃).

Explanation:
Dispersion Forces are present and developed by those compounds which are non-polar in nature. In given statement n-Pentane and n-Hexane both are non-polar in nature as the electronegativity difference between Hydrogen atoms and Carbon atoms is less than 0.4.
When non-polar molecules approaches each other, a Dipole is induced in one of them, this step is known as Instantaneous Dipole, This generated Dipole on approaching another non-polar molecule induces dipole in it and the process propagates. Hence, creating intermolecular interactions.

8 0

3 years ago

Read 2 more answers

Please help! Consider the following reaction: 3H2S (g) + 3O2 (g)  2 SO2 (g) + 2H2O (g) If O2 was the excess reagent, 4.15 mol o

iren [92.7K]

Answer:

91.8 %

Explanation:

Data given:

Amount of H₂S = 4.15 mol

Amount of water (H₂O) = 68.55 g

Amount of oxygen O₂ = in excess

Percent yield of reaction water (H₂O) of water = ?

Reaction Given:

2H₂S (g) + 3O₂ (g) ----------> 2SO₂ (g) + 2H₂O (g)

Solution:

First we look for the theoretical yield by looking in the reaction

2H₂S (g) + 3O₂ (g) ----------> 2SO₂ (g) + 2H₂O (g)

As oxygen is in the excess so only H₂S amount act as limiting reagent.

2H₂S (g) + 3O₂ (g) ----------> 2SO₂ (g) + 2H₂O (g)

2 mol 2 mol

to convert amount of H₂O from moles to grams

mass in grams = no. of moles x molar mass

Molar Mass of H₂O = 2(1) + 16 = 18 g/mol

Put values in above equation

mass in grams = 2 mol x 18 g/mol

mass in grams = 36 g

So,

3H₂S (g) + 3O₂ (g) ----------> 2SO₂ (g) + 2H₂O (g)

2 mol 36 g

As from the reaction it is clear that 2 mole of H₂S gives 36g H₂O then 4.15 mole will give how many grams of water

Apply unity formula

2 mol of H₂S ≅ 36 g of H₂O

4.15 mol of H₂S ≅ X g of H₂O

Do cross multiplication

X g of H₂O = 36 g x 4.15 mol / 2 mol

X g of H₂O = 74.7 g

So theoretical yield = 74.7 g of H₂O

Formula used for percent yield

percent yield = actual yield / theoretical yield x 100

Put values in above equation

percent yield = 68.55 g / 74.7 g x 100

percent yield = 91.8 %

***Note

For SO₂ it is important to have actual yield. and implement same work.

6 0

4 years ago

Using Newton’s laws of motion, describe the motion of a roller coaster and analyze the forces acting on the roller coaster at di

Illusion [34]

We can apply Newton's third law of motion in roller coaster.

Explanation:

If we are planning to make a roller coaster with elevations and turn then we need to apply newton’s law of motions, kinetic energy and potential energy.

Newton’s third law of motion says that “ for every action, there is an equal and opposite reaction”. Newton’s third law of motion applies between the tract and ride vehicles.

If we neglect the air resistance and friction, Roller coaster car will always experience two types of forces which are gravitational force and normal force. The normal force is acting perpendicular to the track and gravitational for is also acting downwards.

Whenever the tracts get moving the gravitational force is attracting roller coaster to downward. So this will get accelerates. In the majority of the roller coasters, the hill will decrease with height as the train moves along the tract.

3 0

4 years ago

What distinguishes a mixture from an impure substance?

Leno4ka [110]

<u>Answer:</u> Mixture can be separated into its components but impure substance cannot be separated into components.

<u>Explanation:</u>

A mixture is defined as a combination of two or more different substances in which the component substances are individually distinct. The substances can be separated by physical processes. The separation dos not involve any chemical process because no new substance is being formed.

Impure substance is defined as a substance which can be mixture of elements, compounds or elements and compounds. The substances cannot be separated by physical means but can only be separated by chemical means.

3 0

3 years ago

Sugar is easily soluble in water and has a molar mass of 342.30 g/mol. what is the molar concentration of a 252.6 ml aqueous sol

lions [1.4K]

0.811 M is the molar concentration of a 252.6 ml aqueous solution prepared with 70.3 g of sugar.

<h3>Define molarity of a solution.</h3>

Molarity (M) is the amount of a substance in a certain volume of solution. Molarity is defined as the moles of a solute per litres of a solution.

Given data:

252.6 mL = 0.2526 L

Next, we shall determine the number of moles of the sugar. This can be obtained as follow:

Molar mass of sugar = 342.30 g/mol.

Mass of sugar = 70.3 g

Mole of sugar =?

Mole = $\frac{mass}{molar \;mass}$