Answer:
The number of positive charges in nucleus of an atoms are equal to the atomic number and also positive charges are equal to the negative charges which are electrons in neutral atom.
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.
Electron:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol= e⁻
Mass= 9.10938356×10⁻³¹ Kg
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Neutron and proton:
Neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P⁺
Symbol of neutron= n⁰
Mass of proton=1.672623×10⁻²⁷ Kg
Mass of neutron=1.674929×10⁻²⁷ Kg
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.
For example
The carbon have six protons and six neutrons so its atomic mass is 12 amu and atomic number is six.
Grams (g) is much lighter than kilograms (kg)
The answer is B or the second answer
Answer:
Explanation:
A homogeneous mixture consists of one single phase while a heterogeneous mixture consists of two or more phases.
Answer:
Explanation:
Diethyl malonate is more acidic than monocarbonyl compounds (pKa=13) due to their alpha hydrogens being attached to two carbonyl groups. Thus, the <u>malonic ester is easily converted to its enolate ion by reaction with sodium ethoxide in ethanol</u>. The product of the alkylation of the malonic ester leaves a <u>hydrogen atom acid in an alpha position</u>, so the alkylation process can be repeated a second time to produce a dialkylated malonic ester.
In this case, when urea is treated with diethyl malonate in the presence of sodium ethoxide base,<u> the second alkylation step occurs intramolecularly</u> to generate a cyclic product, barbituric acid.
