Answer : The correct option is, (B) Hydrochloric acid(HCl)
Explanation :
Rust is an iron oxide, which is formed by the reaction of iron with oxygen in the presence of water.
As we know that the rust is an iron oxide (base) which is removed by an acid.
As per given options, the acid used to remove the rust from the metal is hydrochloric acid and not sulfuric acid because sulfuric acid is an oxidizing agent which oxidizes the metal more.
While the other options, ammonia and sodium hydroxide are a base.
Hence, hydrochloric acid is used to remove rust from metal.
Answer:
option(d)
Explanation:
The frequency of a wave is the property of the source of wave.
The velocity of all the electromagnetic waves is same as the speed of light. It only changes as the light passes through one medium to another.
The frequency is defined as the number of waves coming out from the source in 1 second.
As the frequency of wave increases, the number of wave coming per second increases.
So, the number of waves passing by increases but the speed remains same.
Option (d)
1. clavicle = collarbone
2. vertebrae = backbone
3. scapula = shoulder blade
4. femur = thigh
5. humerus = upper arm
6. patella = kneecap
7. cranium = skull
8. tibia = lower leg
9. radius/ulna = forearm
10. phalanges = fingers/toes
Answer:
D, Im not very sure about this but I would say D
Explanation:
I tried
