Answer:
The answer is in the explanation.
Explanation:
A buffer is defined as the aqueous mixture of a weak acid and its conjugate base or vice versa. Buffers are able to avoid the pH change of a solution when strong acid or bases are added (As NaOH).
Based on the experiment, it is possible that the solution Z was a buffer and Y another kind of solution. For this reson, pH of the solution Y changes much more than the pH of solution Z changes despite the amount of NaOH added is the same in both solutions.
Answer:
Core electrons are the electrons in an atom that are not valence electrons and therefore do not participate in bonding. The number of valence electrons of an element can be determined by the periodic table group of the element
Explanation:
Answer:
The types of cells at work in the human body
Explanation:
Rudolf Virchow was a German physician who is known as the father of modern pathology. He contributed to the development of the cell theory by concluding that all cells come from preexisting cells. This led to the conclusion that diseases occur at the cellular level, which allowed scientists to diagnose diseases more accurately.
Considering that Virchow analyzed human cells, the image that Tumu would be most likely to use in his assignment is the one of the types of cells at work in the human body.
Answer: Option (c) is the correct answer.
Explanation:
A chemical reaction is defined as the reaction where a chemical bond will break in order to form a new bond due to the formation of a new substance.
For example, 
Here, NaCl is the new substance that is formed. A chemical reaction will always bring change in chemical composition of a substance.
The production of hydrogen gas from water, the tarnishing of a copper penny, charging a cellular phone and burning a plastic water bottle are all chemical reactions.
Whereas a reaction where no change in chemical composition of a substance takes place is known as a physical reaction.
For example, chopping a log into sawdust will change the shape but it will not bring any change in chemical composition of the substance.
Thus, we can conclude that in the following list, only chopping a log into sawdust is not an example of a chemical reaction.
The axial positions the bond angle is 120 degrees and in equatorial positions the bond angle is 90 degrees.
Functional groups on central atom gets reduce if lone pairs are added.
Explanation:
The number of lone pairs and base pairs of electrons tells the geometry of the molecule.
VSEPR Theory helps to know the lone pairs and bond pair electrons on the centre atom of the molecule.
Example of molecule containing 5 electron pairs can have four bond pairs and 1 lone pair.
eg: Cl
the repulsion is shown as
lp-lp> lp-bp>bp-bp
These are in equatorial position because of the repulsion of lone pairs.
It can have 2 lone pairs and 3 bond pairs. eg. Xe
Lone pairs in this is also in equatorial position as
lp-lp> lp-bp> bp-bp
In axial positions the bond angle is 120 degrees
in equatorial positions the bond angle is 90 degrees, due to the repulsion in lone pair of electrons.
If 1 lone pair is there it can be replaced by bonding with hydrogen.
If 2 lone pairs are there then bonding with oxygen is there. The covalent bond is formed.