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4 years ago

Who invented carbon element?

Chemistry

1 answer:

igor_vitrenko [27]4 years ago

8 0

Carbon discovered in Prehistoric times.. Discoverer will probably never be known

You might be interested in

What is the total charge of the nucleus of a carbon atom?<br> (1) –6 (3) +6<br> (2) 0 (4) +12

NeX [460]

Carbon atomic number ⇒ 6
Carbon mass number ⇒ 12.

Carbon atomic number - Carbon mass number = number of neutrons.
12 - 6 = 6 neutrons.

Proton charge ⇒ +1

The total charge of the nucleus of a carbon atom ⇒⇒⇒ +6.

So the naswer is (3) +6

3 0

3 years ago

Energy of motion is referred to as CA. thermal energy B. electrical energy C. potential energy D. kinetic energy

Natali [406]

It’s, D. Kinetic Energy.

Explanation: Energy associated with an object’s motion is called kinetic energy. A speeding bullet, a walking person, and electromagnetic radiation like light all have kinetic energy.

Hope this helped ;)

8 0

3 years ago

How many moles are in 7.2x10^15 atoms of Pb?

fiasKO [112]

<h3>Answer:</h3>

1.2 × 10⁻⁸ mol Pb

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[Given] 7.2 × 10¹⁵ atoms Pb

<u>Step 2: Identify Conversions</u>

Avogadro's Number

<u>Step 3: Convert</u>

[DA] Set up: $\displaystyle 7.2 \cdot 10^{15} \ atoms \ Pb(\frac{1 \ mol \ Pb}{6.022 \cdot 10^{23} \ atoms \ Pb})$
[DA] Multiply/Divide [Cancel out units]: $\displaystyle 1.19562 \cdot 10^{-8} \ mol \ Pb$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 2 sig figs.</em>

1.19562 × 10⁻⁸ mol Pb ≈ 1.2 × 10⁻⁸ mol Pb

6 0

3 years ago

Lead(II) oxide from an ore can be reduced to elemental lead by heating in a furnace with carbon. Calculate the expected yield of

Lelu [443]

Answer:

53kg is the expected yield of lead

Explanation:

Firstly, in order to solve this question, we need to write the equation of reaction correctly. This is as follows:

PbO(s) + C(s) ---> Pb(l) + CO(g)

We proceed from here. We should get the limiting reactant but this can only be obtained by getting the number of moles of each reactant present.

The formula to use across all boards is that the number of moles is the mass of each of the reactant divided by the molar mass of each of the reactant.

For PBO, mass is 57kg = 57000g

Molar mass of PBO = 223.20g/mol

The number of moles is thus 57,000/223.2 = 255.37 moles

For carbon, mass is also 57kg = 57000g

Molar mass is 12g/mol

Number of moles of carbon = 57000/12 = 4750 moles

From the number of moles, we can see that the number of moles of Carbon is greater than that of PbO. This means that PbO is the limiting reagent.

Hence we use it to calculate percentage yield.

The number of moles of lead formed is the same of number of moles of lead oxide = 255.37 since we have mole ratio of 1 to 1

The molar mass of lead is 207.20g/mol

The mass of lead formed is = moles of lead formed * molar mass of lead = 207.20 * 255.37 = 52,912g which is approximately 53kg

Hence the expected yield is 53kg

6 0

3 years ago

Complete the sentence.

Leno4ka [110]

Answer:

6, double

Explanation:

Hex- is a prefix for number 6.

Ene- is a suffix for a double bond.

7 0

3 years ago