... change its form, such as the phases of matter, or convert into energy.
The appropriate answer is C. Both are formed by gravitational forces. The first picture shows an elliptical galaxy. These galaxies can be round, nearly spherical or flattened disks. They contain very little dust or gas and the stars contained here are older than stars in other galaxies. The second picture shows a spiral galaxy that has a center made up of a thick mass of material and has flattened arms that rotate around the center.
Galaxies are formed from the gravitational pull of massive objects in space. Some galaxies from around super massive black holes (spiral) or a group or collection or cluster of stars.
This is the case because in a fission reaction you are essentially having a particle or neutron split apart and or interact with an unstable nuclei, causing smaller nuclei to form upon the collision, which would most likely cause a chain reaction to occur, since a great deal of energy is involved in breaking apart the nuclei, more energy would be released if this is done, compared to electrons being transferred to form chemical bonds, or causing electrons to be dislodged from a chemical covalent bond.
Answer: Option (a) is the correct answer.
Explanation:
Ionic bond is formed by the transfer of electrons.
Metals contain more number of electrons, so in order to attain stability they easily lose excess of electrons. This results in the formation of positive ions.
Thus, metals form ionic bonds.
Hence, we can conclude that metals lose their valence electrons and form positive ions.
Answer:
Below are the statements which are true about the structure of the periodic table:
B: The inner transition elements are placed at the bottom of the periodic table for easy viewing.
D: The distribution of electrons in energy levels is responsible for the shape of the periodic table.
Explanation:
Point A:
As we know that in a periodic table there are 7 period s and 18 groups. So, the number of periods is evidently lesser than the number of groups. But the shape of periodic table is regular and rectangular so point A is false.
Point B:
The inner transition elements or -f block elements are put at the bottom for easy viewing. These are the elements that have the valence electrons only in the f-orbital's. Therefore, they are placed separately at the bottom side of the table so that they can be easily viewed or studied from there. So, point B is true.
Point C:
If we talk about option C, then it is very clear and true that considering a rectangular shape of the periodic table, the groups are vertically arranged and periods are horizontally arranged, therefore it is false.
Point D:
Atoms of all elements have definite electronic distribution in different energy levels like s, p d or f. This is a very prominent feature of periodic tale that elements are divided in specific blocks, s, p, d and f based on their electronic configurations. Therefore, it is true.
Point E:
We also know that no. of metals in a periodic table are more than the no. of non metals like almost 91 out of 118 elements are metals in periodic table. Therefore, the point E "Nonmetals take up more than half the area of the periodic table." is false.
Hope it helps!
