Answer: EL ZINC ES EL ELEMENTO PURO PORQUE NO HA REACCIONADO CON NINGÚN OTRO METAL O NO METAL. EL SULFURO DE ZINC ES UN COMPUESTO PORQUE HA REACCIONADO CON EL AZUFRE PARA HACER EL COMPUESTO.
english:
ZINC IS THE PURE ELEMENT BECAUSE IT HAS NOT REACTED WITH ANY OF OTHER METAL OR NONMETAL. ZINC SULPHIDE IS A COMPOUND BECAUSE IT HAS REACTED WITH SULPHUR TO MAKE COMPOUND.
Answer:
compound
Explanation:
a substance made from two or more different elements that have been chemically joined. Examples of compounds include water (H2O), which is made from the elements hydrogen and oxygen, and table salt (NaCl), which is made from the elements sodium and chloride.
Answer:
Incorrect statement is (b).
Explanation:
Option (a) : There is an inverse relation between the time and the frequency. The time taken depends on the frequency of the number of oscillations. Statement 1 is correct i.e. the time taken by any point of the wave to make one complete oscillation does not depend on the amplitude.
Option (b) : Speed of a wave is given by the product of its frequency and wavelength. It is not necessary that doubling the wavelength of the wave will halve its frequency as speed depends on the medium.
Option (c) : Doubling the amplitude has no effect on on the wavelength as amplitude does not depends on its wavelength.
Option (d) : Since,
Speed is directly proportional to the frequency and wavelength. So, doubling the frequency of the wave will double its speed. So, the incorrect statement is (b).
Area of land drained by a water system
Concave mirrors can make a real image.when the object is away from the mirror it is called real image and when the object is closer to the mirror it is called virtual mirror.