Answer: Option (c) is the correct answer.
Explanation:
When a system is open then there will be exchange of energy between the system and surrounding.
Whereas when a system is closed then there will be no exchange of energy, that is, thermal energy will not flow into the atmosphere.
Thus, we can conclude that a sealed calorimeter is a closed system because thermal energy is not transferred to the environment.
a scale-model mound made of the same materials that make the real hill
False Alkaline earth metals is group 2
Answer:
270g
Explanation:
Given parameters:
Concentration of NaOH = 1.5M
Volume = 4.5L
Unknown
Mass of NaOH added = ?
Solution:
To solve the problem, we need to find the number of moles of the NaOH first;
Number of moles = concentration x volume
Number of moles = 1.5 x 4.5 = 6.75mol
Now;
Mass = Number of moles x molar mass
Molar mass of NaOH = 23 + 16 + 1 = 40g/mol
Mass = 6.75 x 40 = 270g
