If element x has 55 protons how many electrons does it have

Answer:

The correct option is;

Scientist propose explanations that can be explained by examining evidence

Explanation:

A scientists makes an hypotheses based on possible natural processes to explain the origin and/or the nature of the characteristics of a natural observation. The scientist then source more data and information to put their hypotheses to test. Due to the fact that an hypotheses is based on observable  processes and/or mechanisms, the given hypotheses can be further tested by other scientists through the use of their individually sourced data. From the result of the assessment, the hypotheses can be either accepted or rejected to enable the better clarification of the hypotheses when accepted or the development of a new hypotheses when rejected.

Molar mass of a molecule is the sum of the atomic mass of the individual elements in the molecule.  

Atomic mass of Pb = 207  amu

Atomic mass of N = 14  amu

Atomic mass of O = 16  amu

Here amu stands for atomic mass unit

Molar mass of Pb(NO₃)₂ = 207 + [14 + (16 x 3)] x 2  

                                         = 207 + 28 + (48) x 2 = 331 g/mol  

is the substance that can be decomposed by chemical means.

Further Explanation:

The pure form of matter is defined as substance but the mixture is termed as the combination of atoms and molecules.

Classification of substances:

(a). Element

It is a type of pure substance and is the simplest form that cannot be broken down by any chemical means. Copper, iron, and aluminium are some of the examples of elements.

(b) Compound

It is composed of two or more different elements that are held together by chemical bonds. These can be decomposed into their respective constituents. Compounds have no similarity in properties with those of their constituent particles. NaCl, and are examples of compounds.

(1) Ammonia contains one nitrogen and three hydrogen atoms so it is a compound. Since compounds can be decomposed chemically, ammonia is also decomposed by chemical means.

(2) Oxygen (O) is an element so it is the simplest form in which it can exist. Therefore it cannot be decomposed by chemical means.

(3) Phosphorus (P) is an element so it is the simplest form in which it can exist. Therefore it cannot be decomposed by chemical means.

(4) Silicon (Si) is an element so it is the simplest form in which it can exist. Therefore it cannot be decomposed by chemical means.

Learn more:

1. Give an example of a two-phase mixture: brainly.com/question/838401
2. Which sample is a pure substance? brainly.com/question/2227438

Answer details:

Grade: High School

Subject: Chemistry

Chapter: Elements, compounds, and mixtures

Keywords: substance, ammonia, oxygen, phosphorus, silicon, element, compound, chemical means, decomposed, broken down, simplest form.

Final answer:

Ammonia is a compound composed of nitrogen and hydrogen, and as such, can be chemically decomposed into these elements. Oxygen, phosphorus and silicon, being elements, cannot be decomposed by chemical means.

Explanation:

In the context of chemistry, a substance can be decomposed by chemical means if it is a compound. Compounds are composed of two or more different elements and can be broken down into those elements through chemical reactions. In the given options, (1) ammonia is a compound, composed of nitrogen and hydrogen elements. Therefore, ammonia can be chemically decomposed into its constituent elements. In contrast, oxygen, phosphorus, and silicon are all elements, which means they cannot be decomposed further by chemical means.

Learn more about Decomposition of Substances here:

brainly.com/question/31730584

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