Answer:
4)experiments with cathode ray tubes
Explanation:
when sufficiently high voltage is applied across the electrods, current starts flowing through a stream of particles moving in the tube the negative electrode (cathode) to the positive electrode (anode). These were called Cathode Rays or Cathode Ray Particles
Answer: Hydrogen gas will be given off
Explanation:
Whenever a metal reacts with an acid, a salt of the metal is formed and hydrogen gas is given off.
For instance: The reaction of Zinc metal on Hydrochloric acid.
Zn(s) + 2HCl(aq) ---> ZnCl2(aq) + H2(g)
From the equation provided, hydrogen gas is given off as a by-product
C. Rubbing the balloon against your hair
Answer:
i think C the higher the frequency the lower the energy of light.
The balanced chemical equation for the above reaction is as follows;
2Ca + O₂ --> 2CaO
stoichiometry of Ca to O₂ is 2:1
this means that 2 mol of Ca reacts with 1 mol of O₂.
If O₂ is the limiting reactant,
4 mol of O₂ should react with (4x2) - 8 mol of Ca
however only 7.43 mol of Ca is present. Therefore Ca is the limiting reactant.
7.43 mol of Ca reacts with - 7.43/2 = 3.715 mol of O₂
therefore there's excess O₂₂ remaining after the reaction
Since Ca is the limiting reactant, it is fully used up in the reaction and there is no Ca remaining after the reaction is completed.
