Answer:
In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.
Explanation:
(copied from Google)
Answer: The mass in
atoms of zinc is 0.405 g.
Explanation:
Given: Atoms of zinc = 
It is known that 1 mole of every substance contains
atoms. So, the number of moles in given number of atoms is as follows.

As moles is the mass of a substance divided by its molar mass. So, mass of zinc (molar mass = 65.39 g/mol) is calculated as follows.

Thus, we can conclude that the mass in
atoms of zinc is 0.405 g.
Answer:
The best answer would be:
C. The scientific method was followed because the experiment tested the hypothesis and produced reliable results.
Explanation:
The purpose of an experiment is to test the hypothesis. It is true that having an experimental group and a control group was following the scientific method but the data gathering and documentation was also part of the scientific method. So the best answer would be C.
Writing the question is not necessary. It is merely part of forming a hypothesis. The scientific method does not require many scientists to perform the experiment, but it does require that the experiment be repeatable, so it can be tested again.
Answer:
No, Mercury can actually cause poisoning. That is why other metals, such as Alkaline metals, are used in making batteries
Answer:
Reducing sugars are absent
Explanation:
Benedict's solution is an substance used in testing sugars. It is mixture of sodium carbonate, sodium citrate and copper(II) sulfate pentahydrate. It can be used instead of Fehling's solution in testing for the presence of reducing sugars.
Reducing sugars contain the -CHO group. If there is no colour change after the addition of Benedict's solution, then we can conclude that reducing sugars are absent.