The electron configuration of an element is 1s^ 2 2s^ 2 2p^ 2 How many valence electrons does the clement have? (1 point )

What is the National Suicide rate for Teens?

Butoxors [25]

I think it is 11% I read it on a article on msn.

4 0

3 years ago

The compound known as diethyl ether, commonly referred to as ether, contains carbon, hydrogen, and oxygen. A 1.376 g sample of e

hoa [83]

Answer:

The answer to your question is: C₄H₁₀O

Explanation:

Data

CxHyOz

mass sample : 1.376 g

mass CO₂ = 3.268 g

mass H₂O = 1.672 g

Process

Reaction

CxHyOz + O₂ ⇒ CO₂ + H₂O

1.- Calculate the moles and mass of carbon

Molecular mass CO₂ = 44g

44 g of CO₂ -------------- 12 g of C

3.268 g of CO₂ -------- x

x = (3.268 x 12) / 44

x = 0.891 g of Carbon

12 g of carbon ----------- 1 mol

0.891 g of C ---------- x

x = (0.891 x 1) / 12

x = 0.0743 moles of carbon

2.- Calculate the moles and mass of hydrogen

18 g of water --------------- 2 g of H

1.672 g of H₂O ------------ x

x = (1.672 x 2) / 18

x = 0.186 g of hydrogen

1 g of hydrogen ------------ 1 mol of H

0.186 g of H ------------ x

x = (0.186 x 1) / 1

x = 0.186 moles of H

3.- Calculate the mass of Oxygen and its moles

Mass of Oxygen = 1.376 - 0.891 - 0.186

= 0.299 g of O₂

Moles of Oxygen

16 g of Oxygen ---------------- 1 mol

0.299 g of O ----------------- x

x = (0.299 x 1) / 16

x = 0.019 moles of Oxygen

4.- Divide by the lowest number of moles

Carbon 0.0743/ 0.019 = 3.9 ≈ 4.0

Hydrogen 0.186/ 0.019 = 9.7 = 10

Oxygen 0.019/ 0.019 = 1

5.- Write the empirical formula

C₄H₁₀O

4 0

3 years ago

A mixture contains NaHCO3 together with unreactive components. A 1.75 g sample of the mixture reacts with HA to produce 0.561 g

Lynna [10]

Answer:

$\%NaHCO_3=61.2\%$

Explanation:

Hello.

In this case, since the undergoing chemical reaction is only between the sodium bicarbonate and the acid HA:

$NaHCO_3+HA\rightarrow NaA+H_2O+CO_2$

For 0.561 g of yielded carbon dioxide (molar mass 44 g/mol), the following mass of sodium bicarbonate (molar mass 84 g/mol) that reacted was:

$m_{NaHCO_3}=0.561gCO_2*\frac{1molCO_2}{44gCO_2} *\frac{1molNaHCO_3}{1molCO_2} *\frac{84gNaHCO_3}{1molNaHCO_3} \\\\m_{NaHCO_3}=1.071g$

Considering the 1:1 mole ratio between CO2 and NaHCO3. Finally, the percent by mass of NaHCO3 is computed by dividing the mass of reacted NaHCO3 and t the mixture:

$\%NaHCO_3=\frac{1.071g}{1.75g}*100\%\\ \\\%NaHCO_3=61.2\%$

Best regards.

5 0

3 years ago

Where is greatest amount of fresh water in the world found? A. wetlands B. rivers C. glaciers D. lakes

WINSTONCH [101]

Answer:

C. Glaciers

Explanation:

Over 68 percent of the fresh water on Earth is found in icecaps and glaciers, and just over 30 percent is found in ground water. Only about 0.3 percent of our fresh water is found in the surface water of lakes, rivers, and swamps.

Hope this helps!

All the love, Ya boi Fraser :)

7 0

2 years ago

Read 2 more answers

3. Given the following equation:

miskamm [114]

Answer:

4.767 grams of KCl are produced from 2.50 g of K and excess Cl2

Explanation:

The balanced equation is

2 K+ Cl2 --->2 KCI

Here the limiting agent is K. Hence, the amount of KCl will be calculated as per the mass of 2.50 gram of K

Mass of one atom/mole of potassium is 39.098 grams

Number of moles is 2.5 grams = $\frac{2.5}{39.098} = 0.064$

So, 2 moles of K produces 2 moles of KCL

0.064 moles of K will produces 0.064 moles of KCl

Mass of one molecule of KCl is 74.5513 g/mol

Mass of 0.064 moles of KCl is 4.767 grams

4 0

2 years ago