Answer:
A :an atom seeks to fill its outer shell of electrons
Explanation:
Reactions between atoms occur due the desire of an atom to fill their outer shell electrons.
The driving force for many interatomic bonding is the tendency to have completely filled outer energy levels like those of the noble gases.
- The various interatomic interaction which leads to chemical reaction is in a bid for the atoms to be isoelectronic in the outer energy level with the noble gases.
- This is achieved by gaining, losing or sharing of electrons.
A chemical reaction is a process in which one or more substances are changed into new substances.
An example of a chemical reaction is when metal rusts.
Answer:
d. eon, era, period, epoch
Explanation:
The geological time scale has been made so that the scientists can have a practical system about the classification of geological time, thus everything that has happened throughout it. The geological time unites have been defined in accordance with important events that have happened, thus marking their end or beginning. These events can be mass extinctions, catastrophes, climate patterns, domination of certain species etc. The longest of these time units is the eon, lasting for more than half a billion years, and up to 2 billion years. The era comes as the second longest time unit, lasting for several hundred million years. The period lasts for several tens of million years, and the epoch is the smallest unit, lasting for few million years, or several hundred thousand years.
Well Prokaryotes usually consist of only one chromosone.
Answer:
The correct option is b
Explanation:
Phospholipids are lipids that contains a phosphate group, which forms the "head" of the molecule and is hydrophilic (water loving). The "tail" of phospholipids is made of two fatty acids which are hydrophobic (water fearing). The phospholipid in the cell membrane acts as a selectively permeable barrier that regulates what goes in and out of the cell <u>thereby protecting the cell from some external molecules and ions</u>.