Help me plzz I need help can someone help

Violet light has a wavelength of 6. 80E-7 m. What is the frequency?

Sever21 [200]

Answer:

violet has a frequency of 668-789 THz :)

Explanation:

5 0

2 years ago

35 points to help me i wrote the definition up top for this i just need help using it in a Example/Sentence

dmitriy555 [2]

In order for a cellular device to operate, it requires battery power, otherwise known as energy.

or you can do this

Us humans consume food so that we can have the sufficient energy to accomplish tasks.

5 0

3 years ago

Based on the results of testing colorless solutions with indicators, which solution is most acidic?

sertanlavr [38]

A solution in which methyl orange is red indicates the most acidic substance.

<h3>What is an Indicator?</h3>

This is defined as a substance that gives a visible sign, usually by a colour change when a chemical species is added.

On litmus paper, the redder the color is, the more acidic it is which was why methyl orange changing to darker red signifies most acidity.

Read more about Indicator here brainly.com/question/1918667

5 0

3 years ago

You mix 200. mL of 0.400M HCl with 200. mL of 0.400M NaOH in a coffee cup calorimeter. The temperature of the solution goes from

GuDViN [60]

Answer : The enthalpy of neutralization is, 56.012 kJ/mole

Explanation :

First we have to calculate the moles of HCl and NaOH.

$\text{Moles of HCl}=\text{Concentration of HCl}\times \text{Volume of solution}=0.400mole/L\times 0.200L=0.08mol$

$\text{Moles of NaOH}=\text{Concentration of NaOH}\times \text{Volume of solution}=0.400mole/L\times 0.200L=0.08mol$

The balanced chemical reaction will be,

$HCl+NaOH\rightarrow NaCl+H_2O$

From the balanced reaction we conclude that,

As, 1 mole of HCl neutralizes by 1 mole of NaOH

So, 0.08 mole of HCl neutralizes by 0.08 mole of NaOH

Thus, the number of neutralized moles = 0.08 mole

Now we have to calculate the mass of water.

As we know that the density of water is 1 g/ml. So, the mass of water will be:

The volume of water = $200mL+200L=400mL$

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1g/ml\times 400mL=400g$

Now we have to calculate the heat absorbed during the reaction.

$q=m\times c\times (T_{final}-T_{initial})$

where,

q = heat absorbed = ?

$c$ = specific heat of water = $4.18J/g^oC$

m = mass of water = 400 g

$T_{final}$ = final temperature of water = $27.78^oC=273+25.10=300.78K$

$T_{initial}$ = initial temperature of metal = $25.10^oC=273+27.78=298.1K$

Now put all the given values in the above formula, we get:

$q=400g\times 4.18J/g^oC\times (300.78-298.1)K$

$q=4480.96J$

Thus, the heat released during the neutralization = -4480.96 J

Now we have to calculate the enthalpy of neutralization.

$\Delta H=\frac{q}{n}$

where,

$\Delta H$ = enthalpy of neutralization = ?

q = heat released = -4480.96 J

n = number of moles used in neutralization = 0.08 mole

$\Delta H=\frac{-4480.96J}{0.08mole}=-56012J/mole=-56.012kJ/mol$

The negative sign indicate the heat released during the reaction.

Therefore, the enthalpy of neutralization is, 56.012 kJ/mole

8 0

3 years ago

Which of the following is NOT a characteristic of a strong acid?

juin [17]

Answer:

a and c

Explanation:

4 0

3 years ago