All categories

2 years ago

Which in the following best describe carbon

Chemistry

2 answers:

kirill [66]2 years ago

6 0

I think the answer is brittle

Alina [70]2 years ago

4 0

I just know it’s not conductive or brittle

You might be interested in

Pleaseeeeeee hlepThe half-life of cobalt-60 is 5.26 years. After 10.52 years, 5 grams of a 20-gram sample will remain.

vladimir1956 [14]

The half-life of cobalt-60 is 5.26 years. After 10.52 years, 5 grams of a 20-gram sample will remain is TRUE

Explanation:

Mass of cobalt = 20 g

Half-life = 5.26 years

Mass remains after 10.52 years = 5 g

This can be solved by using given below formula, $m(t)=m_{o}\left(\frac{1}{2}\right)^{\frac{l}{5.26}}$

$m_{0}$ = initial mass

t = number of years from when the mass was m_0

m(t) = remaining mass after t years

Number of half-lives = $\frac{\text { Time elapsed }}{\text { Half -life }}$

Number of half-lives = $\frac{10.52 \text { years }}{5.26 \text { years }}$

Number of half-lives = 2

At time zero = 20 g

At first half-life = $\frac{20\ g}{2}$ = 10 g

At second half life = $\frac{10\g}{2}$ = 5 g

The given statement is true.

4 0

2 years ago

Calculate the mole fraction of the total ions in an aqueous solution prepared by dissolving 0.400 moles of CaI2 in 850.0 g of wa

Evgesh-ka [11]

Answer:

0.00840

Explanation:

The computation of the mole fraction is as follow:

As we know that

Molar mass = Number of grams ÷ number of moles

number of moles = Number of grams ÷ molar mass

Given that

Number of moles of CaI2 = 0.400

And, Molar mass of water = 18.0 g/mol

Now Number of moles of water is

= 850.0 g ÷ 18.0 g/mol

= 47.22 mol

And, Total number of moles is

= 0.400 + 47.22

= 47.62

So, Molar fraction of CaI2 is

= 0.400 ÷ 47.62

= 0.00840

4 0

3 years ago

Select all that apply. Using your periodic table of the elements which chemical symbols indicate an element?

tatuchka [14]

Answer:

O, I, Ca

Explanation:

4 0

3 years ago

Jai besoi daide

JulijaS [17]

Answer:

i dont know what you are saying

Explanation:

????????????

4 0

2 years ago

Ethanol, C2H6O, is most often blended with gasoline - usually as a 10 percent mix - to create a fuel called gasohol. Ethanol is

weeeeeb [17]

Answer:

This means 463 grams of ethanol would provide less amount of energy

Explanation:

Step 1: Data given

Heat of combustion of ethanol = 326.7 kcal/mol

The heat of combustion of octane = 1.308*10³ kcal/mol

Mass of octane = 463 grams

Molar mass octane = 114.23 g/mol

Molar mass ethanol = 46.07 g/mol

Step 2: Calculate moles octane

Moles octane = mass octane / molar mass octane

Moles octane = 463 grams / 114.23 g/mol

Moles octane = 4.05 moles

Step 3: Calculate energy of combustion of 4.05 moles octane

Combustion of 1 mol octane gives us: 1.308 * 10³ kcal/mol

Combustion of 4.05 moles octane gives us 4.05 * 1.308 * 10³ kcal/mol = 5.30 * 10³ kcal

This means the combustion reaction of 463 grams of octane gives us 5.30 * 10³ kcal

Step 4:

Heat of combustion of ethanol = 326.7 kcal/mol

OR in words: combustion of 1 mol ethanol gives us 326.7 kcal energy

Moles ethanol = 463 grams / 46.07 g/mol

Moles ethanol = 10.05 moles

Since combustion of 1 mol ethanol gives us 326.7 kcal

10.05 moles ethanol will give us = 10.05 * 326.7 = 3283.3 kcal = 3.28 * 10³ kcal

5.30 * 10³ kcal > 3.28 * 10³ kcal

This means 463 grams of ethanol would provide less amount of energy

3 0

3 years ago