Q.1- Which non-metal is used to disinfect water? (1)
Q.-2-Name two major metals which are present in fertilizers and enhance the growth of plants. (1)
Q.3-Why are bells made of metals? (2)
Q.4- Paheli bought a statue made up of copper. To her surprise, it acquired a dull green coating after a couple of months. Explain the reason. (3)
Q.5-Give reasons for the following. (2 x 4 = 8)
(a) Aluminium foils are used to wrap food items.
(b) Immersion rods for heating liquids are made up of metallic substances.
(c) Copper cannot displace zinc from its salt solution.
(d) Sodium and potassium are stored in kerosene.
Q.6- Can you store the lemon pickle in an aluminum utensil? Explain. (3)
Q.7- What happens when- (2)
(a) Dilute sulphuric acid is poured on a copper plate?
PLEASE ANSWER THIS I WILL MARK BRAINLIEST
Answers
Answer:
1) Chlorine
2) Urea and Zinc
3) To hear the sound
4) Because it has turned in oxide form by mixing with oxygen
5)a) Aluminium is not much costly
b) They are malleable
c)It has higher resistance
d) They have high power
6) No
7) Copper plate become gold plate
Answer: Q.1 Chlorine is one of the most commonly used disinfectants for water disinfection.
Q2. Two major non metals that enhance the growth of plants as constituents of fertilizers are NITROGEN and PHOSPHORUS. Nitrogen helps in the leaf development and the green color of leaves is due to it. Phosphorus helps in the development of seeds and fruits and also as disease resistant.
Q3. The bell is made from bronze - an alloy consisting of 78 percent copper and 22 percent tin. The molten copper and tin is mixed by experts like Rudolf Perner, who know exactly how the metals react to heat." ... And the casting of a new bell is a fascinating process that draws crowds of spectators.
Q4. The statue made of copper will get a dull green coating after a couple of months due to the oxidation of copper and other chemical reactions. When exposed to air and under moisture, copper reacts with water and oxygen.
Q5. Aluminium is malleable, soft and does not react with food items, so it is used to wrap food items.
(b) Metals are good conductor of heat and electricity, so immersion rods are made up of metallic substances.
(c) Metals are good conductor of heat and electricity. So immersion rods are made of metallic substance.
(d) Copper is less reactive than zinc. Therefore copper cannot displace zinc from its salt solution.
Q6. Lemon pickle cannot be stored in Al foil as the pickle is acidic in nature which reacts with Al metal liberating hydrogen gas and this can lead to spoiling of the pickle.
Q7. (a) a) When dilute sulphuric acid is poured on a copper plate, no reaction takes place due to less reactivity of copper.
HOPE IT HELPED YOU
PLEASE MARK ME AS BRAINLIEST