Answer:
D) atomic radii increase from top to bottom of a group
Explanation:
Atomic radii trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Other options are incorrect because,
A) atomic radii increase from left to right across the period
Correct = atomic radii decreases from left to right across the period
B) ionization energy increases from top to bottom within a family
Correct = ionization energy decreases from top to bottom within a family
C) electronegativity decreases from left to right across a period
Correct = electronegativity increases from left to right across a period
Hello!
This is false!! It is the other way around. They usually have a very high melting point. For example table salt is around 800deg C which is approx just under 1500deg F.
Hope this helps. Thank you
Answer:
Metals have high densities, high melting points, are malleable and ductile, and can conduct heat and electricity.
Hope this helps as well! :)
Given data:
Distance travelled (d)= 200.0 m
Time taken (t) = 21.7 s
To determine:
The average speed in km/hr
Calculation:
Convert distance from m to km
1000 m = 1 km
200.0 m = 1 km * 200.0 m/1000 m = 0.2 km
Convert time from sec to hours
3600 sec = 1 hour
21.7 sec = 1 hour * 21.7 sec/3600 sec = 6.027 *10^-3 hrs
Speed is defined as the amount of distance travelled per unit time
Speed = distance/time = 0.2 km/6.027*10^-3 hr
= 33.18 km/hr (or 33.2 km/hr)