Question:
how many significant figures are in the measurement 0.0056 ke?
a. four
b. two
c. five
d. three
answer:
b. two
physical change
particles retain there composition and identity
there is no change in there chemical properties of the substance
the chemical changes should be the other two.
If it is wrong I'm truly sorry.
Explanation:
A period 4 element is one of the chemical elements in the fourth row (or period) of the periodic table of the elements.
...
Period 4 element.
Hydrogen Rubidium
Strontium
Yttrium
Zirconium
Niobium
