Answer:
The average atomic mass is 86.565
Explanation:
An element's average atomic mass is the sum of the products of the masses of the isotopes of the element and their percentage abundance divided by 100
The average atomic mass of the Element X is given as follows;
Isotope type 1 (85.91) ×
Isotope 
Abundance (%) Mass /100 Portion of average mass
Type 1 67.25 × 85.91 ÷ 100 57.774475
Type 2 32.75 × 87.91 ÷ 100 28.790525
Average atomic mass = 86.565
The average atomic mass = 86.565.
Your answer is the last option, the explosion of fireworks. This is because all of the other options are physical changes because they don't change the substance, they only affect it in some way. However the explosion of a firework clearly changes a substance inside the initial 'rocket' into fireworks.
I hope this helps!
Explanation:
Formula to calculate refractive index of n is as follows.
n = 
where, 
= mole fraction of A
= mole fraction of B
= refractive index of A
= refractive index of B
Hence, putting the given values into the above formula as follows.
n =
1.5248 = 
........ (1)
Also, it is known that 
= 1
and, 
......... (2)
Now, put equation (2) in equation (1) as follows.
1.5248 = 
1.5248 = 
= 0.467
And, the value of is calculated as follows.
= 
= 0.533
Hence, mole percentage of A will be calculated as follows.
Mole % of A = 
= 
= 46.7%
Thus, we can conclude that the mole percent of A in their mixture is 46.7%.
SI unites are based on multiplying or dividing by 10, 100, 1,000, 10,000 (and so on...) depending on the unit you're solving for.
The conversion from Celsius degrees to Kelvin temperature is:
T in Kelvin = T in °C + 273.15
The freezing temperature of water is known to be 0°C; then its equivalent in Kelvin is:
Freezing temperature = 0 + 273.15 = 273.15 K.
So, the answer is 273.
