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:
2.8 L
Explanation:
From the question given above, the following data were obtained:
Number of mole (n) = 0.109 mole
Pressure (P) = 0.98 atm
Temperature (T) = 307 K
Gas constant (R) = 0.0821 atm.L/Kmol
Volume (V) =?
The volume of the helium gas can be obtained by using the ideal gas equation as follow:
PV = nRT
0.98 × V = 0.109 × 0.0821 × 307
0.98 × V = 2.7473123
Divide both side by 0.98
V = 2.7473123 / 0.98
V = 2.8 L
Thus, the volume of the helium gas is 2.8 L.
Answer: shining a bright light on the object and testing for decomposition
Decomposition is the separation of a molecule into its elements or simpler compounds.
And a chemical property is the ability of a
substance to combine or to become one or more substances.
Then, testing the ability of an object for decomposition is testing a chemical property.
Answer:
(A) first order reaction
Explanation:
A first order reaction is a type of reaction in which the rate of the reaction depends only on the concentration on one of the reactants. Since A is the only reactant we have, it is right to deduce that this reaction is a first order reaction.
Note: while the order of this reaction is 1, its molecularity is 2. The molecularity of a reaction is the number of moles of reactants that is actually reacting.
(B) is wrong
This is because a zero order reaction is one in which the rate of reaction is not influenced by the concentrations of the reactants and hence remains constant irrespective. Since we were not furnished with this idea in the question, it is only right that we reject this answer.
(C) is wrong.
C is outrightly wrong as we have only one reactant.
(D) is wrong
We have only one reactant.
Answer:
x
Explanation:
becaue neutron equal to mass num -atomic num
