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11 months ago

Match each element to the number of electrons in its valence shell.

Chemistry

1 answer:

irinina [24]11 months ago

6 0

Answer:

C: 4

H: 1

Mg: 2

O : 6

Explanation:

You can quickly find out the number of valence electrons by looking at where the element is on the periodic table and referring to the table that is attached.

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Analyse the temperature versus time graph of water, given below.

BlackZzzverrR [31]

Answer:

Phase C - Liquid State

Phase E - Gaseous State

Explanation:

Usually, in phases of water, we have the following;

When temperature is less than zero, it is said to be in its solid phase as ice.

When temperature is between 0 to 100, we can say it is in the liquid phase as water.

When temperature is above 100°C, It is said to be in the gaseous phase as vapour.

From the diagram;

Phase C is the only liquid state because it falls between temperature of 0°C and 100°

Also, only phase E is in the gaseous phase because the temperature is above 100°C.

3 0

2 years ago

A sample of 8.5 g NH 3 on oxidation produces 4.5 g of NO. Calculate the percent yield.

yanalaym [24]

Answer:

nvnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnv

Explanation:

3 0

3 years ago

how many molecules of sulfuric acid are in a spherical raindrop of diameter 6.0 mm if the acid rain has a concentration of 4.4 *

Vitek1552 [10]

Answer:

The number of moles =

$Moles=4.97\times 10^{-8}$

The number of molecules =

$Molecules = 2.99\times 10^{16}$

Explanation:

Volume of the sphere is given by :

$V=\frac{4}{3}\pi r^{3}$

here, r = radius of the sphere

$radius=\frac{diameter}{2}$

$radius=\frac{6.0}{2}$

Radius = 3 mm

r = 3 mm

1 mm = 0.01 dm (1 millimeter = 0.001 decimeter)

3 mm = 3 x 0.01 dm = 0.03 dm

r = 0.03 dm

("volume must be in dm^3 , this is the reason radius is changed into dm"

"this is done because 1 dm^3 = 1 liter and concentration is always measured in liters")

$V=\frac{4}{3}\pi 0.03^{3}$

$V=\frac{4}{3}\pi 2.7\times 10^{-5}$

$V=1.13\times 10^{-4}dm^{3}$

$V=1.13\times 10^{-4}L$ (1 L = 1 dm3)

Now, concentration "C"=

$C=4.4\times 10^{-4}moles/liter$

The concentration is given by the formula :

$C=\frac{moles}{Volume(L)}$

This is also written as,

$Moles = C\times Volume$

$Moles=1.13\times 10^{-4}\times 4.4\times 10^{-4}$

$Moles=4.97\times 10^{-8}$ moles

One mole of the substance contain "Na"(= Avogadro number of molecules)

So, "n" mole of substance contain =( n x Na )

$N_{a}=6.022\times 10^{23}$

Molecules =

$Molecule=4.97\times 10^{-8}\times 6.022\times 10^{23}$

$Molecules = 2.99\times 10^{16}$ molecules

7 0

3 years ago

What are the building blocks of proteins?

bogdanovich [222]

Answer:

amino acids

Hope this helps:)

7 0

3 years ago

Read 2 more answers

In the following reaction, how many grams of ammonia (NH3) will react with 27.8 grams of nitric oxide (NO)? 4NH3 + 6NO → 5N2 + 6

Rzqust [24]

4NH₃ + 6NO → 5N₂ + 6H₂O

mol of NO = $\frac{mass of NO}{Molar Mass of NO}$

= $\frac{27.8 g}{30.01 g / mol}$

 = 0.93 mol

Based on the balance equation mole ratio of NH₃ : NO is 4 : 6
= 2 : 3

If mol of NO = 0.93 mol

then mol of NH₃ = $\frac{0.93 mol * 2}{3}$

= 0.62 mol

Mass of ammonia = mol × molar mass

= 0.62 mol × 17.03 g/mol

= 10.54 g

Therefore B is the best answer

3 0

3 years ago

Read 2 more answers