Answer:
The value of y = 5.1478
Explanation:
The linear equation is an equation obtained when a linear polynomial is equated to zero. When the solution obtained on solving the equation is substituted in the equation in place of the unknown, the equation gets satisfied.
The given equation: 5.3 x 10- (y)(2y) = 0
⇒ 53 - 2y² = 0
⇒ 2y² = 53
⇒ y² = 53 ÷ 2 = 26.5
⇒ y = √26.5 = 5.1478
Answer: 4.18925 kJ heat is needed to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.
Explanation:
Temperature of Solid
Melting temperature of Solid 
Temperature of liquid 
Specific heats of solid ethanol = 0.97 J/gK
Specific heats of liquid ethanol = 2.3 J/gK
Heat required to melt the the 25 g solid
at 159 K
= 159 K - 138 K = 21 K

Heat required to melt and raise the temperature of
upto 223 K
= 223 K - 159 K = 64 K

Total heat to convert solid ethanol to liquid ethanol at given temperature :
(1kJ=1000J)
Hence, 4.18925 kJ of heat will be required to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.
I’d say A. They are theoretical in the fact that they have not been observed directly, but have been confirmed to exist through experimentation.
Answer:
<em>YOU</em> use <em>YOUR OWN WORDS</em>
Explanation:
Have a good day! :)