All categories

3 years ago

Which statements are correct about silicon?

Chemistry

1 answer:

ki77a [65]3 years ago

4 0

Answer:

A. Metalloid

E. Has similar properties as Ge

F. Belongs to Period 3

Explanation:

Silicon is the 14th element on the periodic table. Its unit is SI. Its properties straddles between those of metals and non-metals and it is described as a non-metal.

It's atomic weight or mass number is 28u. It has an atomic number of 14 i.e in its neutral state, the number of protons and electrons are equal to 14.

Silicon belongs to the 4th group and the 3rd period on the periodic table. Elements in the same group share similar chemical properties. The elements in Si group are: C, Ge, Sn and Pb. The properties of Si is similar to these elements because they all have a valency of 4. Across the period, the properties varies this is why Si would have a very different property from Al and P.

You might be interested in

Provide the mass number of Fe, which has 29 neutrons

zmey [24]

Answer:

55.845 u

Explanation:

Fe, iron, has 29 neutrons and a atomic mass of 55.845 u

6 0

3 years ago

Assuming the volumes are additive, what is the [Cl−] in a solution obtained by mixing 297 mL of 0.675 M KCl and 664 mL of 0.338

Elden [556K]

Answer: The concentration of chloride ions in the solution obtained is 0.674 M

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (in mL)}}$ .....(1)

For KCl:

Molarity of KCl solution = 0.675 M

Volume of solution = 297 mL

Putting values in equation 1, we get:

$0.675=\frac{\text{Moles of KCl}\times 1000}{297}\\\\\text{Moles of KCl}=\frac{(0.675mol/L\times 297)}{1000}=0.200mol$

1 mole of KCl produces 1 mole of chloride ions and 1 mole of potassium ion

Moles of chloride ions in KCl = 0.200 moles

For magnesium chloride:

Molarity of magnesium chloride solution = 0.338 M

Volume of solution = 664 mL

Putting values in equation 1, we get:

$0.338=\frac{\text{Moles of }MgCl_2\times 1000}{664}\\\\\text{Moles of }MgCl_2=\frac{(0.338mol/L\times 664)}{1000}=0.224mol$

1 mole of magnesium chloride produces 2 moles of chloride ions and 1 mole of magnesium ion

Moles of chloride ions in magnesium chloride = $(2\times 0.224)=0.448mol$

Calculating the chloride ion concentration, we use equation 1:

Total moles of chloride ions in the solution = (0.200 + 0.448) moles = 0.648 moles

Total volume of the solution = (297 + 664) mL = 961 mL

Putting values in equation 1, we get:

$\text{Concentration of chloride ions}=\frac{0.648mol\times 1000}{961}\\\\\text{Concentration of chloride ions}=0.674M$

Hence, the concentration of chloride ions in the solution obtained is 0.674 M

5 0

3 years ago

HELP ME PRETTY PLEASE FAST FOR BRAINLIEST

Mumz [18]

Answer:

M is increased loudness

O is decreased loudness

N is decreased pitch

P is increased pitch

Louder soundwaves ten to have longer and deeper waves visa versa.

Increased pitch tends to have shorter soundwaves. visa versa

8 0

3 years ago

1. What is the probability of rolling a five on one die three times in a row?

Bad White [126]

1/6 x 1/6 x 1/6= solve the rest

7 0

3 years ago

Please help thank you

maxonik [38]

Answer:

$K=1.7x10^{-3}$

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to solve this problem by firstly setting up the equilibrium expression for the given reaction, in agreement to the law of mass action:

$K=\frac{[NO]^2}{[N_2][O_2]}$

Next, we plug in the given concentrations on the data table to obtain:

$K=\frac{(0.034)^2}{(0.69)(0.98)}\\\\K=1.7x10^{-3}$

Regards!

5 0

3 years ago