Since the density of water is 1 g /mL, hence there is 100
g of H2O. So total mass is:
m = 100 g + 5 g = 105 g
=> The heat of reaction can be calculated using the
formula:
δhrxn = m C ΔT
where m is mass, C is heap capacity and ΔT is change in
temperature = negative since there is a decrease
δhrxn = 105 g * 4.18 J/g°C * (-2.30°C)
δhrxn = -1,009.47 J
=> However this is still in units of J, so calculate
the number of moles of NaCl.
moles NaCl = 5 g / (58.44 g / mol)
moles NaCl = 0.0856 mol
=> So the heat of reaction per mole is:
δhrxn = -1,009.47 J / 0.0856 mol
δhrxn = -11,798.69 J/mol = -11.8 kJ/mol
Answer:
The answer is
<h2>5.0 g/cm³</h2>
Explanation:
The density of a substance can be found by using the formula
From the question
mass = 35 g
volume = 7 cm³
The density is
We have the final answer as
<h3>5.0 g/cm³</h3>
Hope this helps you
I would say the most correct answer is Kilo, as in kilometers. The store would certainly not be milli, or millimeters away from you, would it now? :)
Hope this helps!
Answer:
V = 134.5 L
Explanation:
Given data:
Number of moles of KClO₃ = 4 mol
Litters of oxygen produced at STP = ?
Solution:
Chemical equation:
2KClO₃ → 2KCl + 3O₂
Now we will compare the moles of KClO₃ with oxygen.
KClO₃ : O₂
2 : 3
4 ; 3/2×4 = 6 mol
Litters of oxygen at STP:
PV = nRT
V = nRT/P
V = 6 mol × 0.0821 atm.L/mol.K × 273 K / 1atm
V = 134.5 L / 1
V = 134.5 L
Answer:
Answer below
Explanation:
Physical changes dont change the chemical makeup of an object. An example would be to tear a piece of paper. Tearing the paper doesnt change how the paper was made chemically
Chemical changes on the other hand do change the chemical makeup of an object. An example of a chemical change would be to bake a cake. The reason being that the chemical makeup of the cake batter is changed so that the actual cake is formed.
