Answer:
Explanation:
Significant figure implies number of digits that are to be considered. Some rules are required to be considered when writing a given expression to an expected significant figures.
So that:
1) 0.00004050 is 4 significant figures
2) 54.7000 is 6 significant figures
3) 1,000.09 is 6 significant figures
4) 0.039 is 2 significant figures
There are 18 numbered groups in the periodic table, and the f-block columns (between groups 3 and 4) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e., the same core charge), as most chemical properties are dominated by the orbital location of the outermost electron. There are three systems of group numbering. The modern numbering group 1 to group 18 is recommended by the International Union of Pure and Applied Chemistry (IUPAC). It replaces two older naming schemes that were mutually confusing. Also, groups may be identified by their topmost element or have a specific name. For example, group 16 is variously described as the oxygen group and as the chalcogens.
This problem is requiring the balanced chemical equation that takes place when copper hydroxide and potassium sulfate are produced when reacting potassium hydroxide with copper sulfate.
<h3>Balancing chemical equations:</h3>
In chemistry, balancing chemical equations is based on the law of conservation of mass, which demands us to have equal number of atoms on both sides of the chemical equation. This can be accomplished by inserting coefficients in front of the chemical species.
For this particular case, we have potassium hydroxide with copper sulfate on the reactants side, however, copper can be copper (I) or copper (II) as it has 1+ and 2+ as its possible oxidation numbers. In addition, copper hydroxide and potassium sulfate as the products. Hence, we can assume this is all about copper (II) so we can write:

As we can see, potassium, hydrogen and oxygen have two atoms each on the products side, but just one on the reactants side; drawback we can overcome by putting a 2 in front of KOH so as to balance it:

Learn more about balancing chemical equations: brainly.com/question/8062886
The answer is B, they differ greatly from the properties of all their elements. For example: Water is non-flamable but it is made from hydrogen, which is highly flammable, and oxygen, a gas that supports combustion.
Answer:
Isotopes have the same number of protons but a different number of neutrons.
Explanation: