Explanation

Formaldehyde (HCHO), also known as methanal

It is an organic compound, the simplest of the aldehydes,

At room temperature, it is a colorless, flammable gas with a pungent smell.

Formula: CH₂O

Molar mass: 30.031 g/mol

Boiling point: -19 °C

Explanation

Formaldehyde contains:

• one carbon atom
• two hydrogen atoms
• one oxygen atom.

The formaldehyde formula is written CH2O or HCHO,

At room temperature, formaldehyde is a colorless, flammable gas that is a distinct, pungent smell.

It is also known as :

• methanal,
• methylene oxide,
• oxymethylene,
• methyl aldehyde
• oxomethane.

Explanation

Lime water when used with butter to form butyric acid can cure acidity.

The butyric acid is acidic.

The lime water (soluble form of calcium hydroxide) is basic.

Acid & base mix & become neutral which cures the acidity

Explanation

Boric acid on heating at 100oC gives HBO2.

On heating orthoboric acid (H3BO3) at 370 K or above,

It changes to metaboric acid (HBO2).

On further heating, this yields boric oxide B2O3.

Additional information:

Orthoboric acid, $H_{3}B{O}_3$ is a white crystalline solid, with soapy touch.

It is sparingly soluble in water but highly soluble in hot water.

Explanation

Methylated spirit is 10% methanol and 90% ethanol

The additives which are present in methanol makes it poisonous and dangerous.

This denatured alcohol is made for industrial purposes or non-drinking uses.  Methylated spirit is also used as a fuel for the burners

and it is also used as a solvent.

Explanation

Paramagnetism is due to the presence of one or more unpaired electrons which are attracted by the magnetic field

Due to their spin, unpaired electrons have a magnetic dipole moment and act like tiny magnets.

Explanation

The molecular Geometry of SF6 (sulfur hexafluoride) is octahedral. 

In this molecule, the central atom i.e. sulphur has a total of six electrons in its valence shell

And in the molecule, we have six fluorine atoms so it shares one electron with each fluorine atom.

So this molecule has six bond pairs and no lone pair.

So its structure is octahedral

The bond angles in sulfur hexafluoride molecules are 90A∘ and 180A∘.

Explanation

Grignard reagent reacts with water to give alkane.

This is because Grignard reagent acts as a strong base that reacts with the active hydrogen of water that is -H of  H2O  to form alkane as shown below :

Explanation

GROUP - 11 (I B) [Copper, Silver and Gold]

Copper, Ag, and Au are known as coinage metals

Because they were used to make coins.

All the metals are noble w.r.t. chemical activity.

Explanation

Dipole moment of H2 =0 ( zero ).

The ionic character exists in H2 molecule but no dipole moment or bond moment exists permanently.

In these diatomic molecules, the shared pair of electrons lies between the nucleus of the two bonded atoms.

Hence, no separation of charges occurs. I.e., these molecules have zero dipole moment.