Answer:
d. The particles of matter are arranged
in different ways for the different
states.
Explanation:
when you hear kinetic think hot or cold
example
water when its hot its a gas and looks different under a microscope
water when its cold its ice and looks different under a microscope
Answer:
magnesium
Explanation:
magnesium is in Group 2, in the periodic table. this means that it has 2 valence electrons. the less valence electrons an element or atom has, the more reactive. Selenium has 6 valence electrons. as a result, Mg is more reactive
Answer: Belongs to the group 2A
Explanation:
As you can see, the first two ionization energies are close and low, meaning that this element ionizates easily.
Not only loses easily the first electron, but the second too
To remove the third electron you requiered a huge amount of energy
Now, elements easily ionizable are the ones from group IA, group 2A and transition metals.
The last ones have mixed characteristics in matter of how many electrons you can remove from them, so they are not a family.
Now the question: group I or group II ?
The elements of group I have low ionization energies for the first electron but high energies for the second ones.
Being all that said, the unknown element belongs to the Group 2A
Okay
Mr (H2O)= 18g
therefore moles of H2O
is 720.8/18= 40.04mol
the ratio of H2 to O2 to H2O is
2 : 1 : 2
so moles of H2 is same as H2O here
H2= 40.04moles
moles of O2 is half
so 40.04 x 0.5
20.02moles
grams of O2 is
its moles into Mr of O2
that's 20.02 x 32 = 640.64g
