Sources of Energy — Science STD 10 — Question

In nature, metal A is found in a free state while metal B is found in the form of its compounds. Which of these two will be nearer to the top of the activity series of metals?

What happens when carbon dioxide gas is passed through lime water:

1. for a short time?
2. for a considerable time?

Write equations of the reactions involved.

In the following set of element, one element does not belong to the set. Select this element and state why it does not belong:
Calcium, Magnesium, Sodium, Beryllium.

Describe an activity with labeled diagram to show that a current carrying conductor experiences a force in a magnetic field.

Write the balanced chemical equation for the following reaction and identify the type of reaction.
Ethene is burnt in the presence of oxygen to form carbon dioxide, water and releases heat and light.

1. What is the colour of ferrous sulphate crystals? How does this colour change after heating?
2. Name the products formed on strongly heating ferrous sulphate crystals. What type of chemical reaction occurs in this change?

What will you observe when dilute ethanoic acid and dilute hydrochloric acid are put on universal indicator paper, one by one? What does it show?

Gregor Mendel’s first law of genetics states “Of a pair of contrasted characters", only one can be represented in a gamete by its internal ‘factor’.

The elements A, B and C belong to groups 1, 14 and 17 respectively of the periodic table.

1. Which two elements will form a covalent compound?
2. Which two elements will form an ionic compound?

The diagram given alongside shows a ray of light entering a rectangular block of glass:

1. Copy the diagram and draw the normal at the point of entry.
2. Draw the approximate path of the ray of light through the glass block and out of the other side.