<span>An atom has 16 protons and 17 neutrons. What is the chemical symbol for the atom? Consult the periodic table.
Question 8 options:
A.33Cl This would be correct.
B.32S
C.33S
D.32Cl
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Answer:
the mas is .291 g
Explanation:
the mass of a object does not change. so when added the substance the beaker. you had the mass of both objects together. you know the mass of the beaker and you know the mass of both. since mass does not change. the beakers mass is still 74.605g. the mass of both objects is 74.896. all you have to do is subtract the mass of the beaker from the total mass. 74.896 - 74.605 equals .291g. so the mass of the unknown substance Is .291g
Answer : C) separate the parts by their properties.
Explanation:
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. Trail is a mixture of various substances which do not react chemically and thus the constituents retain their chemical properties. The substances can be separated by using physical properties.
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. The elements lose their individual chemical properties. The elements can not be separated using physical means.
Solution;
The gas is at STP;
Where; T = 273 K , P = 1 atm
We know that 1 mole of a gas at STP occupies a volume of 22.4 liters .
V1/n1 = V2/n2
n2 = (V2/V1) n1
n2 = (2 l/22.4 l)(1 mole)
n2 = 0.0893 moles
But 1 mole of a compound has 6.022 × 10^23 molecules
Thus, number of molecules = 0.0893 moles × 6.022 ×10^23 molecules
= 5.378 × 10^22 molecules.
