Question
Name two metals which react violently with cold water. Write any three observations you would make when such a metal is dropped into water. How would you identify the gas evolved, if any, during the reaction?
✓
Answer
Sodium and potassium metals react violently with cold water Observations:
- Metal starts moving over the surface of water making a hissing sound.
- Metal starts reacting with water causing little explosions.
- Soon the metal catches fire and starts burning.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Observe the diagram and answer the questions:
i. Which energy is generated from the power plant?
ii. State its source.
iii. Which is more eco-friendly - power generation from coal or power generation from natural gas? Why?
i. Which energy is generated from the power plant?
ii. State its source.
iii. Which is more eco-friendly - power generation from coal or power generation from natural gas? Why?
Answer the following :
(a) In our country, there seems to be lack of awareness regarding reproductive health. Why?
(b) Write the symptoms of disease gonorrhea.
(c) What precautions will you take to maintain reproductive health?
(a) In our country, there seems to be lack of awareness regarding reproductive health. Why?
(b) Write the symptoms of disease gonorrhea.
(c) What precautions will you take to maintain reproductive health?
What are the limitations of energy that can be harnessed from the sea?
What is the maximum number of 60W bulbs that can be run from the mains supply of 220 volts if you do not want to overload a 5A fuse?
Find the heat needed to raise the temperature of a silver container of mass 100 g by 10 °C. (c = 0.056 cal/g.°C)
State the various steps involved in the process of photosynthesis.
Explain the term corrosion with a suitable example.
(OR)
What is corrosion ?
(OR)
What is corrosion ?
Explain the following temperature vs time graph:
Observe the figure 1.3 of transcription given on page 9 in this chapter and answer the following questions:
(1) What is the sequence of nucleotides present on one strand of the DNA?
(2) According to the above sequence on DNA, what will be the transcribed sequence on the mRNA molecule?
(3) Which enzyme is taking part in the above process of transcription?
(1) What is the sequence of nucleotides present on one strand of the DNA?
(2) According to the above sequence on DNA, what will be the transcribed sequence on the mRNA molecule?
(3) Which enzyme is taking part in the above process of transcription?
State two methods of concentration of ores in which the heavy particles of ores can be separated from the light gangue particles by the gravitational method.