CBSE Class X – Science Chemistry + Biology + Physics Exam (Full Syllabus)

hydrogen-containing compound such as glucose is not categorized as acid because it does not produce hydrogen ions or some other ions, when dissolved in water, and consequently does not conduct electricity

HCI, being a polar covalent compound, easily ionses in water to form hydronium (H₃O+) and chloride ions (Cl– ). HCl (a strong acid) ionises completely in water to produce H+ and Cl–  ions. H+ ion dilutes with water molecules to produce hydronium ions.

Both Graphite and diamond being the allotropes of the same element , carbon, have similar chemical properties. So they undergo the same chemical reactions.

Catenation is the property of self-linking of an element by which an atom combines with the other atoms of the same element to form long chains

Flourine has Ǫ electrons in the outermost orbit. Its atom size is the smallest too. Since it is the most electronegative element, it does not lose an electron easily.

The process of digestion begins in the mouth. The mouth contains a digestive enzyme, salivary amylase. This enzyme breaks the starch molecules in the food, into maltose. The absence of amylase in the saliva thus afects the breakdown of starch into simpler sugar molecules.

The lime water turns milky on passing carbon dioxide gas into it due to formation of insoluble calcium carbonate. When the exhaled air rich in carbon dioxide is blown from mouth into test tube, it reacts with lime water (calcium hydroxide) to produce calcium carbonate and water

Budding in which a bud arises from a particular region on a parent body. And after detaching from the parent body the bud grows into a new independent individual

Vegetative propagation is a method of asexual reproduction in some higher plants in which a new plant develops from the vegetative parts of a plant such as a root, stem or leaf.

The character of the cross will be cross fertilization, which is the transfer of pollen from one plant to the stigma of fower; borne on a distinct plant of the same species.

The bluish colour of water in deep sea is due to scattering of light. The fne particles in water scatter mainly blue light having shortest wavelength.

repulsion is noticed only when two bodies have like charges and this means that the bodies must be charged. Hence, repulsion is a true test of electrification

A kilowatt-hour is an amount of energy consumed by a machine working at a steady rate of one kilowatt for one hour. As a result, Joule is a SI unit of energy, but Kilowatt-hour is a Commercial unit.

Brass is not a magnetic material. It is an alloy of copper and zinc

The magnetic field lines inside a long straight solenoid carrying current is in the form of parallel straight lines which indicates that the magnetic field is same at all points inside the solenoid