Answer:
1. (c)
2. (a)
3. (c)
4. (b)
5. (d)
1. (a)
2. (b)
3. (c)
Explanation:
<u>OBSERVATION TYPE</u> :-
1. The elements can be divided into 3 major groups metals, non- metals and metalloids. The rest of the options are also the names of some groups yet fail to be then correct answer. If you were asked to define 18 groups that exist in the periodic table then you'd have selected them. (r u getting me?)
2. Group 1 elements are known as alkali metals
3. Group 2 elements are called alkaline earth metals
4. Group 13 is called Boron Family
5. These are non-metals
i'd have selected Nobel gases had not Hydrogen been there. Excluding Hydrogen all are nobel gases.
<u>C</u><u>O</u><u>N</u><u>C</u><u>L</u><u>U</u><u>S</u><u>I</u><u>O</u><u>N</u><u> </u><u>:</u><u>-</u>
1. The modern periodic table groups the elements into vertical columns, groups, and horizontal rows, groups.
2. Since the question is asking the harmful changes in metals that take place upon reacting with acids, it'll be option (b). as the metals corrode upon being treated with acids which is not of good use to us. the last two options talk bout the uses of this process which wont be "harmful", so the answer is only option (b)
3. Protective layering of various metals like Zn, Al helps prevent corrosion in metals.
Answer:
for differentiation
Explanation:
By gram staining, we can determine about gram-positive and gram-negative bacteria. If bacteria are Gram-positive then for further catalase test perform. If bacteria give catalase-positive then that's mean this bacteria is Staphylococcus. If bacteria give catalase-negative result then that's mean this bacteria is streptococcus.
The bacteria that are catalase-positive for their further identification coagulase test perform if bacteria is coagulase-positive that's mean it is staphylococcus aureus and if it is coagulase-negative that's mean that maybe differentiation saprophyticus or other species.
<span>Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaebacteria kingdom), but this classification is outdated. Archaeal cells have unique properties separating them from the other two domains of life, Bacteria and Eukaryota. hope that helped</span>
Please see the attached file for the correct answer