1) D = 13.6 g / mL
2)ethyl alcohol weighs 158g
3)ρ
_copper = 8.9 g 
Explanation:
1)
D = m / V
=306.0 g / 22.5 mL
D= 13.6 g / mL
2)
density = mass / volume
mass = density × volume
=0.789g /ml × 200.0 ml
M=158g
Ethyl alcohol weighs 158g
3)
ρ (density) = Mass / Volume
ρ
_copper = 1896 g / 8.4cm × 5.5cm × 4.6cm
= 1896g / 212.5 
ρ
_copper=8.9 g 
LiAlH₄ is used as strong reducing agent. The hydride produced acts as a nucleophile and attacks the electrophillic carbon of carbonyl group. In given example two reactions are observed.
Reaction 1: In first step LiAlH₄ when treated with
Ester produces corresponding
Aldehyde and alcohol.
Reaction 2: This aldehyde produced further reacts with LiAlH₄ to give a reduced product (
Alcohols). In this case Butanol is produced.
The reaction schemes are shown as felow,
Answer: A = atomic number = 12
Explanation: A (atomic number) defines the chemical element. It is the numbervof protons or electrons. Neutron numbers may vary, produving isotopes of differing atomic mass. This isotope has atomic mass 28. The atomic number 12 = carbon. C28 does not really exist. If it could be produced it would be radioactive with an almost zero halflife.
Answer:
3.) 51.7 L
Explanation:
To find the volume, you need to use the Ideal Gas Law:
PV = nRT
In the equation,
-----> P = pressure (kPa)
-----> V = volume (L)
-----> n = moles
-----> R = Ideal Gas constant (8.314 kPa*L/mol*K)
-----> T = temperature (K)
First, you need to convert the temperature from Celsius to Kelvin. Then, you can plug the given values into the equation and simplify to find "V".
P = 68.0 kPa R = 8.314 kPa*L/mol*K
V = ? L T = 27.00 °C + 273 = 300 K
n = 1.41 moles
PV = nRT <----- Ideal Gas Law
(68.0 kPa)V = (1.41 moles)(8.314 kPa*L/mol*K)(300 K) <----- Insert values
(68.0 kPa)V = 3516.822 <----- Multiply right side
V = 51.7 <----- Divide both sides by 68.0