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4 years ago

What type of electromagnetic waves does the human eye see as the colors red, blue, or green

Chemistry

1 answer:

Delicious77 [7]4 years ago

5 0

Answer:

Visible light waves

Explanation:

Visible light waves are the only electromagnetic waves we can see. We see these waves as the colors of the rainbow. Each color has a different wavelength. Red has the longest wavelength and violet has the shortest wavelength.

You might be interested in

When metal atoms combine chemically with atoms of other elements, what do they usually do?

Fiesta28 [93]

Answer:

Maybe I know too much chemistry but how the metals (and the non-metals) react depends on where they are in the Periodic Table. The metals in groups I and II over on the far left side are explosively reactive and loose electrons and form ionic bonds. Examples: Na+1 has lost 1 electron and Li+2 has lost 2 electrons. The metals in the higher groups are more confusing but most of them share outer shell electrons and form covalent bonds. Examples: Fe2O3 (rust) where Iron shares 2X3 electrons with Oxygen which shares 3X2 electrons. Confused enough? :-)

The answer you'll be expected to give depends on the subject of the chapter you're studying. If you're studying covalent bonds, then the answer will probably be "form covalent bonds". If you're studying ionic bonds, then the answer will be "lose electrons".

Explanation:

This may not be the answer... I'm sorry if it's not

8 0

3 years ago

commercial cold packs consist of solid NH4NO3 and water. In a coffee-cup calorimeter, 5.60g NH4NO3 is dissolved in 100g of water

fgiga [73]

Answer:

-1.37 kJ/mol

Explanation:

The expression for the calculation of the enthalpy of dissolution of [tex[NH_4NO_3[/tex] is shown below as:-

$\Delta H=m\times C\times \Delta T$

Where,

$\Delta H$ is the enthalpy of dissolution of [tex[NH_4NO_3[/tex]

m is the mass

C is the specific heat capacity

$\Delta T$ is the temperature change

Thus, given that:-

Mass of ammonium nitrate = 5.60 g

Specific heat = 4.18 J/g°C

$\Delta T=17.9-22.0\ ^0C=-4.1\ ^0C$

So,

$\Delta H=-1.25\times 4.18\times 3.9\ J=-95.9728\ J$

Negative sign signifies loss of heat.

Also, 1 J = 0.001 kJ

So,

$\Delta H=-0.096\ kJ$

Also,

Molar mass of [tex[NH_4NO_3[/tex] = 80.043 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{5.60\ g}{80.043 \ g/mol}$

$Moles= 0.06996\ mol$

Thus, $\Delta H=-\frac{0.096}{0.06996}\ kJ/mol=-1.37\ kJ/mol$

6 0

3 years ago

A solution was prepared by dissolving 195.0 g of KCl in 215 g of water. Calculate the mole fraction of KCl. (The formula weight

defon

Answer:

Approximately $0.180$ .

Explanation:

The mole fraction of a compound in a solution is:

$\displaystyle \frac{\text{Number of moles of compound in question}}{\text{Number of moles of all particles in the solution}}$ .

In this question, the mole fraction of $\rm KCl$ in this solution would be:

$\displaystyle X_\mathrm{KCl} = \frac{n(\mathrm{KCl})}{n(\text{All particles in this soluton})}$ .

This solution consist of only $\rm KCl$ and water (i.e., $\rm H_2O$ .) Hence:

$\begin{aligned} X_\mathrm{KCl} &= \frac{n(\mathrm{KCl})}{n(\text{All particles in this soluton})}\\ &= \frac{n(\mathrm{KCl})}{n(\mathrm{KCl}) + n(\mathrm{H_2O})}\end{aligned}$ .

From the question:

Mass of $\rm KCl$ : $m(\mathrm{KCl}) = 195.0\; \rm g$ .
Molar mass of $\rm KCl$ : $M(\mathrm{KCl}) = 74.6\; \rm g \cdot mol^{-1}$ .

Mass of $\rm H_2O$ : $m(\mathrm{H_2O}) = 215\; \rm g$ .
Molar mass of $\rm H_2O$ : $M(\mathrm{H_2O}) = 18.0\; \rm g\cdot mol^{-1}$ .

Apply the formula $\displaystyle n = \frac{m}{M}$ to find the number of moles of $\rm KCl$ and $\rm H_2O$ in this solution.

$\begin{aligned}n(\mathrm{KCl}) &= \frac{m(\mathrm{KCl})}{M(\mathrm{KCl})} \\ &= \frac{195.0\; \rm g}{74.6\; \rm g \cdot mol^{-1}} \approx 2.61\; \em \rm mol\end{aligned}$ .

$\begin{aligned}n(\mathrm{H_2O}) &= \frac{m(\mathrm{H_2O})}{M(\mathrm{H_2O})} \\ &= \frac{215\; \rm g}{18.0\; \rm g \cdot mol^{-1}} \approx 11.9\; \em \rm mol\end{aligned}$ .

The molar fraction of $\rm KCl$ in this solution would be:

$\begin{aligned} X_\mathrm{KCl} &= \frac{n(\mathrm{KCl})}{n(\text{All particles in this soluton})}\\ &= \frac{n(\mathrm{KCl})}{n(\mathrm{KCl}) + n(\mathrm{H_2O})} \\ &\approx \frac{2.61 \; \rm mol}{2.61\; \rm mol + 11.9\; \rm mol} \approx 0.180\end{aligned}$ .

(Rounded to three significant figures.)

8 0

3 years ago

In store A: A box of cotton candy costs 1 dollar, 12 boxes cost 12 dollars. In store B: 12 boxes cost 48 dollars. How much does

pentagon [3]

Answer:

Explanation:

If there is 12 boxs that cost $48, you need to divide the 12 boxs into the $48 to see how many time 12 goes into it to see how much it is. So 48 divided by 12 is 4.

8 0

3 years ago

PLS I NEED HELP ASAP! BRAINLIEST TO FULL ANSWER!!

Serggg [28]

Answer:

CARBON HYDROGEN NYTROGEN OXYGEN

Explanation:

POGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOGPOG

7 0

3 years ago

Read 2 more answers