He rented the horse for 5 hours because $5 x 5 hours = $25
$25 + 12 = $37
Answer:
The ΔH is 5.5 kJ/mol and the reaction is endothermic.
Explanation:
To calculate the ∆H (heat of reaction) of the combustion reaction, that is, the heat that accompanies the entire reaction, you must make the total sum of all the heats of the products and of the reagents affected by their stoichiometric coefficient ( number of molecules of each compound participating in the reaction) and finally subtract them:
Combustion enthalpy = ΔH = ∑H products - ∑Hreactants
In this case:
ΔH = 15.7 kJ/mol - 10.2 kJ/mol= 5.5 kJ/mol
An endothermic reaction is one whose enthalpy value is positive, that is, the system absorbs heat from the environment (ΔH> 0).
<u><em>The ΔH is 5.5 kJ/mol and the reaction is endothermic.</em></u>
One of the most convenient ways of finding or calculating for the
midpoint of the line segment is to get the average of the coordinates of the
points.
Average of abscissa = (0 + 0) / 2 = 0
Average of ordinate = (0 + 15) / 2 = 7.5
Hence, the midpoint of the line segment is equal to (0, 15/2).
The value of the y-intercept is 15/2.
Answer:
the Answer is the second one
Explanation:
mole=mass/molar mass
mole=?
molar mass=142.1g/mole
mass=10.0g
Coulomb's law mathematically is:
F = kQ₁Q₂/r²
we integrate this with respect to distance to obtain the expression for energy:
E = kQ₁Q₂/r; where k is the Coulomb's constant = 9 x 10⁹; Q are the charges, r is the seperation
Charge on proton = charge on electron = 1.6 x 10⁻¹⁹ C
E = (9 x 10⁹ x 1.6 x 10⁻¹⁹ x 1.6 x 10⁻¹⁹) / (185 x 10⁻¹²)
E = 1.24 x 10⁻¹⁸ Joules per proton/electron pair
Number of pairs in one mole = 6.02 x 10²³
Energy = 6.02 x 10²³ x 1.24 x 10⁻¹⁸
= 746.5 kJ
