Define of Radical.
Concept: Language of Chemistry
Tick the most appropriate answer.
Who discovered that radioactive rays are given out by uranium?
- Henri Becquerel
- Marie Curie
- Pierre Curie
- Schmidt
Concept: Atoms: Building Blocks of Matter
Give one example each of which illustrates the following characteristics of a chemical reaction change in state
Concept: Classification of Change: Chemical Changes
How do the following help in bringing about a chemical change?
pressure.
Concept: Classification of Change: Chemical Changes
How do the following help in bringing about a chemical change?
light.
Concept: Classification of Change: Chemical Changes
How do the following help in bringing about a chemical change?
catalyst .
Concept: Classification of Change: Chemical Changes
How do the following help in bringing about a chemical change?
heat.
Concept: Classification of Change: Chemical Changes
Define; catalyst.
Concept: Classification of Change: Chemical Changes
What are (i) positive catalysts and (ii) negative catalysts? Support your answer with one example for each of them.
Concept: Classification of Change: Chemical Changes
Name three biochemical catalysts found in the human body.
Concept: Classification of Change: Chemical Changes
MATCH THE COLUMNAS
| 1. Jpham Dalton | a. Neutrons |
| 2. Atom | b. Model of the atom |
| 3. Chadwick | c.The atomic theory of matter |
| 4. Rutherfrod | d. Positively charged |
| 5. Protons | e. Electricity neutral |
| 6. Nuclear fusion | f. Generator of electricity |
| 7.Gamma -rays | g. High penetrating power |
| h.Energy in sun |
Concept: Atoms: Building Blocks of Matter
TRUE \ FALSE
Elements combine in definite proportions to form compounds.
Concept: Atoms: Building Blocks of Matter
TRUE \ FALSE
Elements having a tendency to accept electrons are called metals
Concept: Atoms: Building Blocks of Matter
TRUE \ FALSE
Neils Bohr gave the theory to explain the arrangement of protons in an atom.
Concept: Atoms: Building Blocks of Matter
TRUE \ FALSE
Cathode rays are a stream of fast moving particles that travel in random directions.
Concept: Atoms: Building Blocks of Matter
WRITE SHORT ANSWER
Define an ionic compound.
Concept: Atoms: Building Blocks of Matter
WRITE SHORT ANSWER
What is radioactivity?
Concept: Atoms: Building Blocks of Matter
WRITE SHORT ANSWER
Name three inert gases.
Concept: Atoms: Building Blocks of Matter
ANSWER IN DETAIL
State the postulates of the Dalton’s atomic theory.
Concept: Atoms: Building Blocks of Matter
ANSWER IN DETAIL
Enlist the features of Bohr’s model of an atom. How did he correct the Rutherford’s model ?
Concept: Atoms: Building Blocks of Matter
