1. Complete the following chart for the following atoms: Element
Mass
number
Number of
electrons
Number of
neutrons
Atomic
Number
(number of
protons)
Potassium
16
56
26
What is the atomic symbol (the nuclide) for the isotope with 15 protons and 16
neutrons? Your answer must be in the form shown:
AX
You must show the correct numbers for A and Z
and have the correct symbol (Z). (3 points)

Explanation:

If there are 15 protons, 15 nuclear particles of unit positive charge, then

Z

=

15

. Now

Z

≡

the atomic number

, and you look at your copy of the Periodic Table, and you find that for

Z

=

15

, the element phosphorus is specified.

But we are not finished. Along with the 15 defining protons, there are also 16 neutrally charged, massive nuclear particles, 16 neutrons, and the protons and neutrons together determine the atomic mass. The isotope is thus

31

P

, which is almost 100% abundant, and an important nucleus for

NMR spectroscopy.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

i think is conclusions.i think so