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Nutka1998 [239]
3 years ago
14

When we reverse a chemical equation,we multiply it's delta H value by

Chemistry
1 answer:
Illusion [34]3 years ago
7 0
Delta H is negated. Multiply by -1
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What is the wavelength (in nm) of
LenKa [72]

Answer:

λ = 0.45×10⁻⁶ m

Explanation:

Given data:

Wavelength of blue light = ?

Frequency of blue light = 6.69×10¹⁴ s⁻¹

Solution:

Formula;

Speed of wave = wavelength × frequency

Speed of wave = 3.00×10⁸ m/s

by putting vales,

3.00×10⁸ m/s = λ × 6.69×10¹⁴ s⁻¹

λ = 3.00×10⁸ m/s / 6.69×10¹⁴ s⁻¹

λ = 0.45×10⁻⁶ m

6 0
3 years ago
Some fertilizer blends contain magnesium nitrate (MgNO3). Suppose that a chemist has 1.24 liters of a 2.13 M solution of magnesi
VLD [36.1K]

The  volume of the new solution is

calculation

by use of the formula

M1V1= M2V2

M1 (molarity 1)  = 2.13 M

V1 (volume 1) = 1.24 l

M2 ( molarity 2) = 1.60 M

V2 (volume 2) = ?

by making V2 the subject of the formula

V2 = M1 V1/ M2

V2=( 1.24  x 2.13)÷ 1.60=  1.651 L

5 0
3 years ago
Which substance can not be broken down by a
Tomtit [17]

Answer:  (3) silicon

Explanation:

Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Silicon (Si)

Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: ethane (C_2H_6), propanone (CH_3COCH_3) and water (H_2O)

7 0
3 years ago
An artifact contains one-fourth as much carbon-14 as the atmosphere. how old is the artifact
Nikolay [14]
<h3><u>Answer;</u></h3>

= 11,460 years

<h3><u>Explanation;</u></h3>
  • <em><u>The half life of Carbon-14 is 5,730 years . Half life is the time taken by a radioactive material to decay by half of its original mass.  Therefore, it  would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams</u></em>

<em>The initial amount of carbon-14 in this case was 1 whole; thus; </em>

<em>1 → 1/2 →1/4</em>

<em>To contain 1/4 of the value, 2 half-lives have passed. </em>

<em>But, 1 half life = 5,730 years</em>

<em>Therefore; The artifact is is therefore: 2 x 5,730 </em>

<em>          = 11,460 years </em>

4 0
3 years ago
Read 2 more answers
Problem Page Question It takes to break a carbon-carbon single bond. Calculate the maximum wavelength of light for which a carbo
Marizza181 [45]

This is a incomplete question. The complete question is:

It takes 348 kJ/mol to break a carbon-carbon single bond. Calculate the maximum wavelength of light for which a carbon-carbon single bond could be broken by absorbing a single photon. Round your answer to correct number of significant digits

Answer: 344 nm

Explanation:

E=\frac{Nhc}{\lambda}

E= energy  = 348kJ= 348000 J  (1kJ=1000J)

N = avogadro's number = 6.023\times 10^{23}

h = Planck's constant = 6.626\times 10^{-34}Js&#10;

c = speed of light = 3\times 10^8ms^{-1}

348000=\frac{6.023\times 10^{23}\times 6.626\times 10^{-34}\times 3\times 10^8}{\lambda}

\lambda=\frac{6.023\times 10^{23}\times 6.626\times 10^{-34}\times 3\times 10^8}{348000}

\lambda=3.44\times 10^{-7}m=344nm    1nm=10^{-9}m

Thus the maximum wavelength of light for which a carbon-carbon single bond could be broken by absorbing a single photon is 344 nm

5 0
3 years ago
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