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 
Answer:
this is difficult but simple to answer
Explanation:
all atoms move in 1 direction no more than 2
<span>7.379 * 10^(-4) is measured, hence prone to error, either human error or via measuring device. In this case,
100 cm = 1 m is written in stone and is unquestionable.
The density of the gold is 19.3 g/cm^3 and could be an approximation.
The approximation is good to at least one night.</span>
<u>Answer:</u> The entropy change of the ethyl acetate is 133. J/K
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

Given mass of ethyl acetate = 398 g
Molar mass of ethyl acetate = 88.11 g/mol
Putting values in above equation, we get:

To calculate the entropy change for different phase at same temperature, we use the equation:

where,
= Entropy change = ?
n = moles of ethyl acetate = 4.52 moles
= enthalpy of fusion = 10.5 kJ/mol = 10500 J/mol (Conversion factor: 1 kJ = 1000 J)
T = temperature of the system = ![84.0^oC=[84+273]K=357K](https://tex.z-dn.net/?f=84.0%5EoC%3D%5B84%2B273%5DK%3D357K)
Putting values in above equation, we get:

Hence, the entropy change of the ethyl acetate is 133. J/K
Answer:
Option B. 2096.1 K
Explanation:
Data obtained from the question include the following:
Enthalpy (H) = +1287 kJmol¯¹ = +1287000 Jmol¯¹
Entropy (S) = +614 JK¯¹mol¯¹
Temperature (T) =.?
Entropy is related to enthalphy and temperature by the following equation:
Change in entropy (ΔS) = change in enthalphy (ΔH) / Temperature (T)
ΔS = ΔH / T
With the above formula, we can obtain the temperature at which the reaction will be feasible as follow:
ΔS = ΔH / T
614 = 1287000/ T
Cross multiply
614 x T = 1287000
Divide both side by 614
T = 1287000/614
T = 2096.1 K
Therefore, the temperature at which the reaction will be feasible is 2096.1 K