All categories

3 years ago

What gives the gem amethyst its purplish color?

Chemistry

2 answers:

Aleks [24]3 years ago

6 0

Answer will be B:Iron

Triss [41]3 years ago

3 0

Structure. Amethyst is a purple variety of quartz (SiO2) and owes its violet color to irradiation, iron impurities (in some cases in conjunction with transition element impurities), and the presence of trace elements, which result in complex crystal lattice substitutions.

You might be interested in

How many moles of hydrogen gas would be needed to react with excess carbon dioxide to produce 99.1 moles of water vapor?

denpristay [2]

It would take 198 mol to produce

5 0

3 years ago

1) How many molecules are there in 985 mL of nitrogen at 0.0° C and 1.00 x 10-6 mm Hg?

RSB [31]

Answer : The number of molecules present in nitrogen gas are, $3.48\times 10^{13}$

Explanation :

First we have to calculate the moles of nitrogen gas by using ideal gas equation.

$PV=nRT$

where,

P = Pressure of $N_2$ gas = $1.00\times 10^{-6}mmHg=1.32\times 10^{-9}atm$ (1 atm = 760 mmHg)

V = Volume of $N_2$ gas = 985 mL = 0.982 L (1 L = 1000 mL)

n = number of moles $N_2$ = ?

R = Gas constant = $0.0821L.atm/mol.K$

T = Temperature of $N_2$ gas = $0.0^oC=273+0.0=273K$

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

$(1.32\times 10^{-9}atm)\times 0.982L=n\times (0.0821L.atm/mol.K)\times 273K$

$n=5.78\times 10^{-11}mol$

Now we have to calculate the number of molecules present in nitrogen gas.

As we know that 1 mole of substance contains $6.022\times 10^{23}$ number of molecules.

As, 1 mole of $N_2$ gas contains $6.022\times 10^{23}$ number of molecules

So, $5.78\times 10^{-11}$ mole of $N_2$ gas contains $(5.78\times 10^{-11})\times (6.022\times 10^{23})=3.48\times 10^{13}$ number of molecules

Therefore, the number of molecules present in nitrogen gas are, $3.48\times 10^{13}$

8 0

3 years ago

Why was Niels Bohr’s atomic model superior to all the earlier models?

gladu [14]

1) it explains about stability of an atom by including stationary state.
2) it explains tge quantization of energy.
3) it gives the concept of angular momentum of a revolving electron.

6 0

3 years ago

Read 2 more answers

Needed help plzzz on this chemistry homework.

mrs_skeptik [129]

Hertz is units for frequency. (waves per second)
wavelength = speed/frequency

if you're given the speed use that to calculate, if not then you can probably assume it's a wave of light and use the speed of light (3x10^8 m/s) to calculate.

wavelength = (3x10^8)/(1.28x10^17)
= 0.000000002 m
= 2.34 nm

5 0

3 years ago

Coffee is decaffeinated industrially using supercritical (sc) CO2. One advantage to using scCO2 is that the polarity of the supe

koban [17]

Answer:

Yes

Explanation:

A supercritical fluid has good properties for both liquid and as for extraction properties, the advantages then include:

The fact that it has a lower viscosity than liquid CO2 allowing it to move through and around coffee beans more thoroughly with creating back pressure
Its density is comparable to that of liquid CO2 meaning there is much CO2 per litre as there is liquid form making it more efficient
It has a higher diffusivity than liquid CO2 which aids with penetration of the coffee beans on a molecular level

This experiment would not work with tea leaves because they also contain caffeine

6 0

3 years ago