Answer:
50
Explanation:
40-10 = 30…...…............
Answer is: c. It is incorrect because sodium phosphate is a compound that has a single composition.
Sodium phosphate is chemical compound composed of atoms connected with chemical bonds.
Pure substance is made of only one type of atom (element) or only one type of molecule (compound), it has definite and constant composition with distinct chemical properties.
Pure substances can be separated chemically, not physically, that is difference between pure substances and mixtures.
Answer:
radius = 156 pm
Explanation:
The relation between radius and edge length of unit cell of BCC is
r=a
/4
Given
a = 360 pm
Therefore
r = r = radius = 360
/4= 155.88 pm
Or
156 pm
Answer:
the wavelength of radiation emitted is 
Explanation:
The energy of the Bohr's hydrogen atom can be expressed with the formula:

For n = 7:


For n = 4


The electron goes from the n = 7 to the n = 4, then :


Wavelength of the radiation emitted:

where;
hc = 1242 eV.nm


$724.73 this would be the answer because if you subtract 320.50 and 86.10 from the 1056.33 then add 75 you get 724.73