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3 years ago

Do you think people had energy a long time ago, before modern times?

Chemistry

1 answer:

yulyashka [42]3 years ago

6 0

Answer:

well i would say no because they never found electricity till later on but there was different types of energy but without them knowing

Explanation:

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Determine the oxidation number for nitrogenin

iris [78.8K]

Answer:

1(a) N = 3

(b) N = 0

(d) N = -2

(2) Molecular formula for benzene is C6H6

Explanation:

1(a) N02 1-

N + (2×-2) = -1

N-4 = -1

N = -1+4 = 3

(b) N2

2(N) = 0

N = 0/2 = 0

N + ( 2×-2) + (-1) = 0

N - 4 - 1 = 0

N - 5 = 0

N = 0+5 = 5

(d) N2H4

2(N) + (4×1) = 0

2N + 4 = 0

2N = 0 - 4 = -4

N = -4/2 = -2

(2) Molcular mass of benzene = 78g/mole = (6×12g of carbon) + (6×1g of hydrogen) = 72+6 = 78g/mole

Therefore, molecular formula for benzene is C6H6

7 0

3 years ago

What volume, in mL, of carbon dioxide gas is produced at STP by the decomposition of 0.242 g calcium carbonate (the products are

damaskus [11]

Answer:

54.21 mL.

Explanation:

We'll begin by calculating the number of mole in 0.242 g calcium carbonate, CaCO3.

This is illustrated below:

Mass of CaCO3 = 0.242 g

Molar mass of CaCO3 = 40 + 12 +(16x3) = 40+ 12 + 48 = 100 g/mol

Mole of CaCO3 =?

Mole = mass /Molar mass

Mole of CaCO3 = 0.242/100

Mole of CaCO3 = 2.42×10¯³ mole.

Next, we shall write the balanced equation for the reaction. This is given below:

CaCO3 —> CaO + CO2

From the balanced equation above,

1 mole of CaCO3 decomposed to produce 1 mole CaO and 1 mole of CO2.

Next, we shall determine the number of mole of CO2 produced from the reaction.

This can be obtained as follow:

From the balanced equation above,

1 mole of CaCO3 decomposed to produce 1 mole of CO2.

Therefore,

2.42×10¯³ mole of CaCO3 will also decompose to produce 2.42×10¯³ mole of CO2.

Therefore, 2.42×10¯³ mole of CO2 were obtained from the reaction.

Finally, we shall determine volume occupied by 2.42×10¯³ mole of CO2.

This can be obtained as follow:

1 mole of CO2 occupies 22400 mL at STP.

Therefore, 2.42×10¯³ mole of CO2 will occupy = 2.42×10¯³ x 22400 = 54.21 mL

Therefore, 54.21 mL of CO2 were obtained from the reaction.

7 0

3 years ago

How spectral lines are formed

Ket [755]

=Spectral lines are produced by transitions of electrons within atoms or ions. As the electrons move closer to or farther from the nucleus of an atom (or of an ion), energy in the form of light (or other radiation) is emitted or absorbed.…

3 0

2 years ago

Read 2 more answers

When solving an equation using Gay-Lussac's law, which of the following steps do not apply? A. List your knowns and unknowns. B.

suter [353]

Answer:

C. Plug the unknowns into the ideal gas law formula.

Explanation:

Gay-Lussac's law states that:

"For a constant mass of an ideal gas kept at constant volume, the pressure of the gas is directly proportional to its absolute temperature"

Mathematically, it can be written as:

$\frac{p_1}{T_1}=\frac{p_2}{T_2}$

where

p1 is the initial pressure

T1 is the initial temperature (in Kelvin)

p2 is the final pressure

T2 is the final temperature (in Kelvin)

Therefore, in order to solve for one of the 4 variables, the following steps must be adopted:

A. List your knowns and unknowns.

B. Convert temperature to kelvin.

D. Solve for the unknown.

While the following step is not needed:

C. Plug the unknowns into the ideal gas law formula.

Because we do not need to use the ideal gas law formula.

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3 years ago

What were the main causes of conflict between the nawab of bengal and the east india company

stich3 [128]

1 The British opposed the succession of Sirajuddaulah

2 The British misued the trade concessions

3 The British attacaked the French settlement of
Chandranagar in Bengal

<span>4 The Incident of Black hole had occured</span>

5 0

3 years ago