SSC (Marathi Semi-English) 10th Standard Board Exam [इयत्ता १० वी] - Maharashtra State Board Question Bank Solutions for Science and Technology 1

Moving from left to right, the size of the atom decreases.

The size of an atom depends on the number of valence electrons.

Write an Explanation.

Atomic radius

Write scientific reason.

In same period, boron and oxygen elements have different atomic size.

Write scientific reason.

Nearsightedness, this defect can be corrected by using spectacles with concave lens.

Write scientific reason.

Space debris can be harmful to artificial satellites.

Some elements and their atomic radii are given here. Arrange them in decreasing order of their atomic radii. Identify which of the above elements is the biggest atom and which is smallest?

Explain the following reaction with their balanced chemical equation.

Hydrogen sulphide reacts with sulphur dioxide.

Write information about the given atomic numbers in the table. 10, 20, 7.

Observe the given below the figure, correct it and explain and write about the concept depicted in this figure.

Given below is a diagram showing a defect of vision. Name the defect of vision and draw an accurately labelled diagram to correct this defect.

Balance the given chemical reaction as per the instructions below.

\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]

Oxidation means losing electrons then what is reduction?

Choose the odd one out and write the reason:

Choose the odd one out and write the reason:

Identify the type of chemical reaction given below:

\[\ce{2Mg + O2 -> 2MgO}\]

Correlate the given sequence:

Hypermetropia : Convex lens : ______ : Concave lens

When hydrogen gas is passed over black copper oxide, a reddish-coloured layer of copper is formed.

Answer the questions that follow based on this reaction.

1. Write the equation.
2. What type of reaction is it?
3. Complete the blanks:
   In this reaction, an oxygen atom goes away from CuO (copper oxide), which means that ______ of copper oxide takes place, whereas a hydrogen molecule takes up an oxygen atom and water (H₂O) is formed, meaning ______ of hydrogen takes place.

Answer the questions based on the equation below:

\[\ce{CH3 - CH2 - OH ->[{[O]}][K2Cr2O7/H2SO4] CH3 - COOH}\]

1. What type of reaction is it?
2. What is the role of the chemical written on the arrow?
3. Give one example of one such type of chemical as in answer (b).

It is recommended to use air tight containers for storing oil for a long time.

Observe the figure whether it is correct or not and explain the phenomenon.