a) Write three uses of non-metals.
b) Oxides of non-metals are acidic in nature. Justify.
c) Explain why sliding friction is less than static friction.
d) What is drag ?
Answers
Answer:
A - ➡️Some non - metals and their uses are listed below :
➡️Oxygen is used for breathing.
➡️Chlorine is used for purifying water.
➡️Phosphorous is used in crackers.
➡️Non - metals like nitrogen is used in fertilizers.
➡️Graphite is used as a good conductor of electricity.
➡️Potassium is used in fertilizers.
➡️Nitrogen is used by plants.
B -Note: Most nonmetal oxides areacidic, but not all. For example, carbon monoxide (CO) is not acidic. Such a molecule readily loses a proton from one of its hydroxy groups because the resulting anion is highly stabilized by the oxygen atoms and the electronegative nonmetal atom. Therefore, it's acidic.
C -The friction between the two surfaces is because of the interlocking of the irregularities of the two surfaces. During sliding, contact points do not get enough time to get interlocked properly. Therefore, less friction. ... This explains why sliding friction is less than static friction.
D -Drag is the aerodynamic force that opposes an aircraft's motion through the air. Drag is generated by every part of the airplane (even the engines!). ... Drag is generated by the difference in velocity between the solid object and the fluid. There must be motion between the object and the fluid.
hopes it helps u ❤️
Answers :-
a. Three uses of non-metals :-
› The most common non-metal which takes part in metabolic activities - Oxygen.
› It makes up for 18% of the human body - Carbon.
› The non-metal used in match sticks and other explosive materials - Phosphorus.
b. Oxides of non-metals are acidic in nature : The non-metal oxides react with water to form acidic solutions which produce H+ ions in solution. That is why, non metallic oxides are acidic in nature.
c. Sliding friction is less than static friction :-
› The friction between the two surfaces is because of the irregularities of the two surfaces. During sliding, contact points do not get enough time to get interlocked properly. Therefore, less friction. This explains why sliding friction is less than static friction.
d. Drag :-
› The force acting opposite to the relative motion of any object moving w.r.t the surrounding fluid. This exists between two fluid layers or a fluid and a solid surface. Refer to the attachment for the formula.
Hope it helps!
