With a physical change you can actually see it change like ice turning into water, then with a chemical change you can't see it change, although within the molecules themselves they change which makes that possible.
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Answer:
They are all the same = 8
Explanation:
Since the symbol of that atom is not give, we can infer from the given number the nature and kind of element we are dealing with.
The number 15.999 rounded up to 16 is the atomic weight of the atom also called the mass number.
Although not peculiar enough, we are certain that this atom is Oxygen.
On the periodic table, elements are arranged based on their atomic numbers.
Atomic number of oxygen = 8 = number of protons
For every neutral atom on the periodic table, the number of protons and electrons are the same
Atomic number of oxygen = number of protons = number of electrons = 8
Number of neutrons = Mass number - atomic number = 16 - 8 = 8
The gram formula mass of P2O5 is 31*2 + 16*5 =142. The mole number of P2O5 is 0.380/142=0.00268 mol. There is 7 atom in one P2O5 molecule. And there is 6.02 * 10^23 molecule per mol. So the answer is 1.13*10^22 atoms.
Jupiter Saturn Mars Earth Sun
Answer:
The three compounds are different compounds
Explanation:
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound A = 1.750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound B = 0.8750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound C = 0.4375 g
According to the law of multiple proportions, when atoms of two different elements react to form compounds, the masses of one of the elements that combines with a fixed mass of the other element are in small whole number ratios.
The ratio of the masses are;
Mass of Nitrogen in Compound B/(Mass of Nitrogen in Compound C = 0.8750/0.4375 = 2
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound C = 1.750/0.4375= 4
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound B = 1.750/0.8750= 2
Given that the masses of Nitrogen in the three compounds are in small whole number ratios, the three compounds, Compound A, Compound B, and Compound C are different compounds.