Answer:
True.
Explanation:
The mass number of an atom can be calculated using no of protons and the no of neutrons.
Mass number = no of protons + no of neutrons
We can rearrange the above formula to find the no of neutrons as follows :
no of neutrons = Mass number - no of protons
or
Neutrons = Mass - protons.
Hence, the given statement is true.
Answer:
Positively Charged
Explanation:
The is a group XVI and period 4 element of the periodic table with similar physical and chemical to that of tellurium and sulfur. Selenium exist in different allotropic forms, which have different solubility including selenate, selenite and selenium in elemental form
The Se ion in selenate has a positive charge of +6, while the selenate ion has a charge of -2
The Se ion in selenite has a charge of +4, while the selenite ion has a negative charge of -2.
The charge of Se in elemental selenium is 0.
Answer:
n = 3.0 moles
V = 60.0 L
T = 400 K
From PV = nRT, you can find P
P = nRT/V = (3.0 mol)(0.0821 L-atm/K-mol)(400 K)/60.0L
P = 1.642 atm = 1.6 atm (to 2 significant figures)
Explanation:
<span>Like dissolves like and unlike repels like. This applies to the polarity of the solutions. Polar dissolves polar and non-polar does not mix with polar solutions. In this case, the polar substance that can mix with water. Sugar and salt can be dissolved through agitation. Oil which is nonpolar is immiscible in water. Hence answer is D. </span>
