7 Valence lectrons I am pretty sure
Answer:
The number of electron in neutral atom of nitrogen are 7.
Atomic mass = 14 amu
Explanation:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
The number of electron in neutral atom of nitrogen are 7.
Thus its atomic number is also 7.
Atomic mass = number of proton + number of neutron
Atomic mass = 7 + 7
Atomic mass = 14 amu
Answer:
Sample A - mixture
Sample B- Mixture
Explanation:
Looking at sample A, we can see that as water was poured over sample A, the sample was separated into its components as the powder disappeared leaving behind a gritty black sand-like material on the surface of the paper. A separation of the mixture has taken place.
In sample B, we can clearly see that it is a mixture because the amount of solid recovered is much less than the total mass of the solid put into the beaker. The sample must have been separated into its components.
Answer : Option B) All atoms of a single substance are identical.
Explanation : The scientist John Dalton proposed the atomic theory which had the postulates as follows.
i) All matter/substances consists of indivisible particles known as atoms.
ii) Atoms of the same element/substance are similar in mass,shape and size, but differ from the atoms of other elements.
iii) Atoms obey the law of conservation of energy which says atoms cannot be created or destroyed.
iv) Atoms of different elements may combine with each other in a fixed, simple, whole number ratios to form any compound atoms.
v) Atoms of same element can combine in ratio with more than one to form two or more compounds.
vi) The atom is considered to be the smallest unit of matter that can take part in a chemical reaction
The reaction is a synthesis reaction.
<h3>What are synthesis reactions?</h3>
Synthesis reactions are one of the numerous reactions in chemistry. These kinds of reactions involve the combination of two atoms of different elements resulting in the formation of new compounds.
Synthesis reactions are sometimes referred to as combination reactions, simply because they have to do with the combination of two or more atoms of different elements into a single compound.
The different elements that combine are referred to as the reactants while the result of the combination is known as the product.
For example: A + B --> AB
In the illustrated reaction, N2 combined with H2 to form NH3. N2 and H2 gases are the reactants while NH3 is the only product formed from the two reactants.
This is a good example of a synthesis/combination reaction.
More on synthesis reactions can be found here: brainly.com/question/24936069
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