Answer:
A. He sent a cathode ray between electrically charged metal plates
For waves:
speed = frequency x wavelength
speed = 3 x 10⁸
frequency = 9192631770 Hz
wavelength = 3 x 10⁸ / (9192631770)
wavelength = 0.033 meters
This wavelength lies in the region of microwaves.
Hey There!
At neutralisation moles of H⁺ from HCl = moles of OH⁻ from Ca(OH)2 so :
0.204 * 42.8 / 1000 => 0.0087312 moles
Moles of Ca(OH)2 :
2 HCl + Ca(OH)2 = CaCl2 + 2 H2O
0.0087312 / 2 => 0.0043656 moles ( since each Ca(OH)2 ives 2 OH⁻ ions )
Therefore:
Molar mass Ca(OH)2 = 74.1 g/mol
mass = moles of Ca(OH)2 * molar mass
mass = 0.0043656 * 74.1
mass = 0.32 g of Ca(OH)2
Hope that helps!
This is an ideal gas problem. The gas inside the balloon is considered ideal. Ideal gas equation is a function pressure, temperature, amount and volume. Note: amount is constant since the balloon ins closed. Pressure is maintained constant since the walls are flexible. Ideal gas equation is: PV=nRT. Put all constant in one side and variables in one.
P/nR=T/V. To find the answer to the question equate the constants of both situation
T1/V1=T2/V2
(25+273.15)/3=(x+273.15)/2
x=-74.38 degC
