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3 years ago

Which among the following electromagnetic radiations have the lowest frequency?

Chemistry

2 answers:

xenn [34]3 years ago

8 0

Answer:

Find g

Write your answer in simplest radical form

insens350 [35]3 years ago

8 0

Lowest to greatest

Microwave
Infra-red
Visible light
Ultra-violet

You might be interested in

How many molecules are in 2.38g of SO2

Murrr4er [49]

2.63 x 10^22 molecules of SO2.

To find this, start with what you know.

2.38g of SO2.

You need to first convert this into Moles since you cannot directly convert grams into molecules. In order to convert grams to moles, you need to find the molecular mass of SO2 - 64.066.

This is because Sulfur has the mass of 32.066 and Oxygen has a mass of 16, but since there are two Oxygen atoms, it's going to be 32.

Your equation should currently appear as so:

2.38g of SO2 = 1 Mole of SO2 / 64.066

Now, you need to convert this to molecules.

Whenever you are searching for molecules without a given amount, you always use Avogadro's number: 6.02 x 10^23

Now, your equation should appear as so:

2.38g SO2 = 1 Mole of SO2 / 64.066 next to a new fraction which is 6.02 x 10^23 / 1 Mole of SO2

Now, multiply across (2.38 x 1 x 6.02 x 10^23). When using Avogadro's number, don't forget to place parenthesis around it.

Then, divide that number by the bottom: 64.066.

Thus, your final answer is that there is 2.63 x 10^22 molecules of SO2.

Don't forget your units!

Hope this helps!

5 0

3 years ago

Substituents on an aromatic ring can have several effects on electrophilic aromatic substitution reactions. Substituents can act

Leya [2.2K]

Answer:

Option A=> -NHCOCH3 and option C = -CH3.

Explanation:

The option A that is -NHCOCH3 is CORRECT because it possesses lone pair of electron with the exception of group 7A elements. It is this lone pair that is used in the Activation of the ring towards substitution. Other groups that falls into this group are; OCH3, alkyls and many others.

Option B that is -COOH is good group for withdrawal of electron through Resonance. Other examples are NO2, -CN and SO3H.

Option C falls to the same category as option A above that is Activation of the ring towards substitution.

Option D falls to the same category as option B above that is group for withdrawal of electron through Resonance.

7 0

3 years ago

At room temperature, a melting solid produces a whitish liquid. A laser beam shined through the liquid is unaffected and produce

navik [9.2K]

The answer is a colloid.

8 0

3 years ago

SOMEONE PLEASE HELP

Zinaida [17]

Answer:

6. 7870 kg/m³ (3 s.f.)

7. 33.4 g (3 s.f.)

8. 12600 kg/m³ (3 s.f.)

Explanation:

6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.

1 kg= 1000g

1m³= 1 ×10⁶ cm³

Mass of iron bar

= 64.2g

= 64.2 ÷1000 kg

= 0.0642 kg

Volume of iron bar

= 8.16 cm³

= 8.16 ÷ 10⁶

$= 8.16 \times 10^{ - 6} \: kg$

$\boxed{density = \frac{mass}{volume} }$

Density of iron bar

$= \frac{0.0642}{8.16 \times 10^{ - 6} }$

= 7870 kg/m³ (3 s.f.)

$\boxed{mass = density \: \times volume}$

Mass

= 1.16 ×28.8

= 33.408 g

= 33.4 g (3 s.f.)

8. Volume of brick

= 12 cm³

$= 12 \times 10^{ - 6} \: m^{3} \\ = 1.2 \times 10^{ - 5} \: m ^{3}$

Mass of brick

= 151 g

= 151 ÷ 1000 kg

= 0.151 kg

Density of brick

= mass ÷ volume

$= \frac{0.151} {1.25 \times 10^{ - 5} } \\ = 12600 \: kg/ {m}^{3}$

(3 s.f.)

6 0

3 years ago

Pb(NO3)2 (aq) + 2 NaI (aq) --> PbI2 (s) + 2 NaNO3 (aq)

Blizzard [7]

Pb(NO3)2 (aq) + 2 NaI (aq) --> PbI2 (s) + 2 NaNO3 (aq)
Starting with with 200.0 grams of Pb(NO3)2 and 120.0 grams of NaI:
A. What is the limiting reagent?
B. How many grams of PbI2 is theoretically formed?
C. How many grams of the excess reactant remains?
D. If 48 grams of NaNO3 actually formed in the reaction, what is the percent yield of this reaction?

8 0

3 years ago