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3 years ago

Is food coloring dissolving in water a chemical change

2 answers:

6 0

Answer: There no chemical change, but there is a physical change.

Reason: When a substance dissolves in water, the substance retains its molecular identity and simply mixes throughout the water

GarryVolchara [31]3 years ago

5 0

No it is still the same element

You might be interested in

Compare and Contrast the two common forces of gravity and friction.

____ [38]

Answer:

Gravity always pulls objects such as a desk, book or person down. Thus, when you jump gravity causes you to land on the ground. Friction, however, doesn't pull objects down

3 0

3 years ago

Calculate the wavelength, in nanometers, of the spectral line produced when an electron in a hydrogen atom undergoes the transit

Lapatulllka [165]

Answer: The wavelength of spectral line is 656 nm

Explanation:

To calculate the wavelength of light, we use Rydberg's Equation:

$\frac{1}{\lambda}=R_H\left(\frac{1}{n_f^2}-\frac{1}{n_i^2} \right )$

Where,

$\lambda$ = Wavelength of radiation

$R_H$ = Rydberg's Constant = $1.097\times 10^7m^{-1}$

$n_f$ = Final energy level = 2

$n_i$ = Initial energy level = 3

Putting the values in above equation, we get:

$\frac{1}{\lambda }=1.097\times 10^7m^{-1}\left(\frac{1}{2^2}-\frac{1}{3^2} \right )\\\\\lambda =\frac{1}{1.524\times 10^6m^{-1}}=6.56\times 10^{-7}m$

Converting this into nanometers, we use the conversion factor:

$1m=10^9nm$

So, $6.56\times 10^{-7}m\times (\frac{10^9nm}{1m})=656nm$

Hence, the wavelength of spectral line is 656 nm

6 0

3 years ago

3. A student carries out the clay-catalyzed dehydration of cyclohexanol starting with 10 moles of cyclohexanol and obtains 500 m

IrinaK [193]

Answer:

$49.45~%$

Explanation:

In this case, we have to start with the chemical reaction:

$C_6H_1_2O~->~C_6H_1_0~+~H_2O$

So, if we start with 10 mol of cyclohexanol ( $C_6H_1_2O$ ) we will obtain 10 mol of cyclohexanol ( $C_6H_1_0$ ). So, we can calculate the grams of cyclohexanol if we calculate the molar mass:

$(6*12)+(10*1)=82~g/mol$

With this value we can calculate the grams:

$10~mol~C_6H_1_0\frac{82~g~C_6H_1_0}{1~mol~C_6H_1_0}=820~g~C_6H_1_0$

Now, we have as a product 500 mL of $C_6H_1_0$ . If we use the density value (0.811 g/mL). We can calculate the grams of product:

$500~mL\frac{0.811~g}{1~mL}=405.5~g$

Finally, with these values we can calculate the yield:

$%~=~\frac{405.5}{820}x100~=~49.45%$ %= (405.5/820)*100 = 49.45 %

See figure 1

I hope it helps!

6 0

3 years ago

5. Water is known to have a composition which is 88.8% oxygen by mass. If you had a

Fantom [35]

Oxygen : 367*0.888=325.896
Hydrogen : 367 - 367*0.888 = 41.104g

4 0

3 years ago

What is an Atomic structure ?

Margaret [11]

Answer: The structure of an atom, theoretically consisting of a positively charged nucleus surrounded and neutralized by negatively charged electrons revolving in orbits at varying distances from the nucleus, the constitution of the nucleus and the arrangement of the electrons differing with various chemical elements.

:) I hope this helped! :)

4 0

4 years ago