C. A new substance is produced. All others are physical changes.
Answer: 28000m/s
Explanation:
Displacement = 700 km due north = 700000m
Time = 25secs
Velocity =?
Velocity = Displacement / Time
V = 700000 / 25 = 28000m/s
Answer:
Across a row, atomic radii decreases.
Explanation:
It decreases because nuclear charge increases across a row, electrons are added to the same shell and shielding remains constant. Therefore the outer electrons are more attracted to the nucleus making the atom smaller.
Get the molarity we need to divide the number of moles of NaCl by the volume of the solution. So, 0.32 moles NaCl divided by 3.4 L, and that gives 0.094 M NaCl.
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Answer:</h2>
Valance electrons can be determined by <u>Group</u> on the periodic table
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Explanation:</h2>
- Valence electrons are the electrons present in the outermost shell of an atom. We can determine the total number of valence electrons present in an atom by checking at its Group in which it is placed in the periodic table. For example, atoms in Groups 1 the number of valence electron is one and for group 2 the number of valence electrons is 2.
- The groups have number of valance electrons as follow:
Group 1 - 1 valence electron.
Group 2 - 2 valance electrons.
Group 13 - 3 valence electrons.
Group 14 - 4 valance electrons.
Group 15 - 5 valence electrons.
Group 16 - 6 valence electrons.
Group 17 - 7 valence electrons.
Group 18 - 8 valence electrons.
Result: No of valence electron can be determined by the group no. of the element.