There are TWO(2) elements present in quicklime. They are calcium and oxygen.

Chemically it is calcium oxide (CaO).

Potassium (K ; Kalium) has Atomic No,. 19 in the Periodic Table.

The '19' tells us that potassium has 19 protons , and 19 electrons.

Potassium's atomic mass is '40' . This tells us the total number of nucleons in the nucleus of the atom.

Nucleons is the collective noun for protons and neutrons.

Since by the Atomic No. we know that there are 19 protons , then the number of neutrons is 40 - 19 = 21 neutrons.

Since protons and neutrons are given an arbitrary value of '1' each, then '40' is the atomic mass of patassium.

NB Some of your correspodents have stated that there is only 1 electron. This is completely wrong ; they have misunderstood. It has 19 electrons.

Potassium , like sodium ; Same Group '1' elements), readily ionise ONE electron

So the to form the ion K^(+). The other 18 electrons remains in the ion.

Since there are 19 protons ( 19 (+) positives, there musr be 19 electrons (19(-) negatives) to maintain an uncharged atom .

When one electron is ionised (lost) the atom becomes an ion and contains 19 (+) & 18(-) = 1(+) ; indicated as '+'

So the atomic symbol is 'K' , but the ionic symbol is 'K^(+)'.

K^(+) is a charged species , a cation. NOT an atom .

NNB Potassium can exhibit ISOTOPES . This is where the number of NEUTRONS can vary.

So the isotopes

K-39 has 20 neutrons, 19 protons, 19 electrons

K-40 has 21 neutrons , 19 protons, and 19 electrons

K-41 has 22 neutrons , 19 protons and 19 electrons.

However, as an example , an isotope of K-41 may ionise to K-41^(+)

This ion would contain 22 neutrons, 19 protons, an 18 elecgtrons.

Notice in ALL cases the number of protons does NOT change. A change in the number of protons means that it is a different element.

Hope that helps!!!!

Yes, carbon-14 isotopes are constantly being absorbed by living organisms through the food they eat or the air they breathe. Once an organism dies, it no longer takes in carbon-14, and the isotope starts to decay at a known rate, allowing scientists to use it for radiocarbon dating.

A positive ion is called a cation. It forms when an atom loses one or more electrons, resulting in a net positive charge. Cations are attracted to anions, which are negative ions, due to their opposite charges.

The electron configuration for chlorine is 1s2 2s2 2p6 3s2 3p5.

The scientific name for MgSO4.7H2O is magnesium sulfate heptahydrate.

The electron configuration of chlorine is 1s2 2s2 2p6 3s2 3p5. This means that chlorine has 17 electrons distributed in its electron shells, with two electrons in the first shell, eight in the second, and seven in the third.

If the magnesium is not polished, there may be impurities or oxides on the surface that could affect the reported mole ratio of oxygen to magnesium. This could result in a higher reported mole ratio due to the presence of excess oxygen-containing compounds on the surface, leading to an inaccurate measurement of the actual ratio of oxygen to magnesium.

Ethyl alcohol (ethanol) is a polar molecule. This is because ethanol contains a polar hydroxyl (-OH) functional group, which creates an uneven distribution of charge within the molecule, leading to positive and negative regions.

Group 17 elements, also known as halogens, give off the most energy when forming negative ions. This is because halogens have a high electron affinity, meaning they strongly attract additional electrons to achieve a stable electronic configuration.

Carbon has 4 valence electrons, allowing it to form 4 covalent bonds to achieve a full outer shell, which is more stable. By sharing electrons with other atoms, carbon can achieve a total of 8 electrons in its outer shell, following the octet rule.

World War 1 pistols were typically made of steel, with some variations having wooden grips. These materials were chosen for their durability and reliability in combat conditions.

The age of the Earth is estimated to be around 4.5 billion years old, based on scientific evidence such as radiometric dating of rocks and fossils. The universe itself is much older, with the Big Bang estimated to have occurred around 13.8 billion years ago.

Ions are atoms that have lost or gained electrons.

The number of protons in an atom remains unchanged but with loss or gain of electrons the charges becomes unbalanced, because the number of electrons is NOT equal to the number of protons.

Ions can be divided into two viz. Cations ( positively charged) and Anions ( negatively charhed(.

Here are some examples.

Sodium atom has 11 protons(+) and 11 electrons(-).

Sodium cation has 11 protons(+) and 10 electrons(-)

If we do a little sum

(+)11 - 10 = (+)1 This is indicated on the sodium cation as

Na(s) = Na^(+) + e^(-)

Similarly

Calcium atom has 20 protons(+) and 20 electrons(-).

Calcium cation has 20 protons(+) and 18 electrons(-)

If we do a little sum

(+)20 - 18 = (+)2 This is indicated on the calcium cation as

Ca(s) = Ca^(2+) + 2e^(-)

Conversely

Chlorineatom has 17 protons(+) and 17 electrons(-).

Chloride anion has 17 protons(+) and 18 electrons(-)

If we do a little sum

(+)17 - 18 = (-)1 This is indicated on the chloride anion as

Cl(g) = Cl^(-) - e^(-)

Similrly

Oxygen atom has 8 protons(+) and 8 electrons(-).

Oxide anion has 8 protons(+) and 10 electrons(-)

If we do a little sum

(+)8 - 10 = (-)2 This is indicated on the chloride anion as

O(g) = O(2-) - 2e^(-)

So ions are charged atoms.

Or

Ions have a charge, Atoms have no charge.

Chemically, charged atoms are no longer atoms but IONS.

The mass number is the number of protons and neutrons added together. Electrons are not counted as part of the mass because while protons and neutrons weigh the same, Electrons weigh virtually nothing compared to them. As far as I can tell, there is no stable atom with a mass of 8.

Covalent.

CH3-Cl = chloromethane

CH2-Cl2 = di-chloromethane

CH-Cl3 - tri-chloromethane

CCl4 = tetrachloromethane.

All the bonds are covalent. However, because of chlorines strong electronegativity , the electrons in the C-Cl bond polarise towards the chlorine.

Nitrogen is a NON-metallic gas. It does not IONISE readily.

However, it has ELECTRON AFFINITY. This means that it will gain electrons to form a negative ion (ANion)

When an atom of nitrogen gains electrons it is shown as 'N^(3-).

The charge on a proton is deemed to be POSITIVE.

NB

The charge on an electron is deemed to be NEGATIVE ( opposite charge)

The charge on a neutron is deemed to be ZERO(NO CHARGE).

the size of atom doesn't decrease regularly due to the reason of lanthanide contraction .there is slightly increase or or almost no increase in atomic radius from 5th to 6th period in transition metal .

Electrically charged atoms are collectively called ION.S.

Once an atom becomes elecgrically charged it is no longer an atom , but an ION.

A positively charged ion is called a CATION e.g. Na^(+)

A negatively charged ion is called an ANION e.g. Cl^(-) .

A molecule of hydrogen, also known as molecular hydrogen, is composed of two atoms of hydrogen. This diatomic molecule is represented by the chemical formula H₂, indicating the two hydrogen atoms are bonded together.

Chlorine gas is a diatomic molecule, Cl2. Two atoms per molecule. A mole contains Avogadro's Number of particles, that being (approximately) 6.02 x 1023. Hence, the number of atoms in one mole of chlorine gas is twice Avogadro's Number, or approximately 1.204 x 1024.

A double bond. Each atom that can share valence electrons has a bonding capacity corresponding to the number of covalent bonds the atom can form. When the bonds form, they give the atom a full complement of electrons in the valence shell. The bonding capacity of oxygen, for example, is 2. ( O=O )

There are 3 atoms in one CO2. So there will be 12 atoms in 4CO2.

The ATOMIC NUMBER (Z) gives the position of an element in the Periodic Table.

It also indicates the number of protons and electrons in an atom of a given element.

Taking two examples;-

Z = 1 ; Hydrogen ; No. of protons = 1, No of electrons = 1

Z = 6 ; Carbon ; No. of protons = 6, No of electrons = 6