<u>Answer:</u> The volume of given amount of ethanol at this temperature is 159.44 mL
<u>Explanation:</u>
Specific gravity is given by the formula:

We are given:
Density of water = 0.997 g/mL
Specific gravity of ethanol = 0.787
Putting values in above equation, we get:

Density is defined as the ratio of mass and volume of a substance.
......(1)
Given values:
Mass of ethanol = 125 g
Density of ethanol = 0.784 g/mL
Putting values in equation 1, we get:

Hence, the volume of given amount of ethanol at this temperature is 159.44 mL
The reaction will be: FeBr2 + K --> KBr + Fe
Balancing gives: FeBr2 + 2K --> 2KBr + Fe
The molar mass of FeBr2 is 55.85 + 2*79.9 = 215.65 g/mol.
We divide 40 g / 215.65 g/mol = 0.185 mol FeBr2
Based on stoichiometry:
(0.185 mol FeBr2)(2 mol KBr/1 mol FeBr2) = 0.370 mol KBr
Answer:
option b
Explanation:
When the energy is released the process is called exothermic reaction. This happens when the bonds are broken in the reactants and the system release energy.
Answer:
<em>Varying frequency</em> between both waves accounts for difference in speed.
Explanation:
The speed of a wave is dependent on four major factors:
- wavelength
- frequency
- medium, and
- temperature
Assuming equal temperature and medium of travel of these sound waves, and given that the wavelength (that is distance of travel) is equal, the only varying factor would be their frequency.
Wave speed is calculated by multiplying the wavelength times the frequency
⇒ Speed = λ * <em>f</em>