Answer:
The snow gains heat to melt (endothermic), then the water releases heat to freeze (exothermic). ... Beaker becomes hot because the reaction is pushing heat out from itself onto .... solidification (ΔHsolidification) when 10.00kJ of energy are lost as 30.00g of water.
Explanation:
To find the number of moles of gas we can use the ideal gas law equation, we dont need to use the mass of gas given as we only have to find the number of moles
PV = nRT
P - pressure - 300.0 kPa
V - volume - 25.0 x 10⁻³ m³
n - number of moles
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature in Kelvin - 27 °C + 273 = 300 K
substituting these values in the equation
300.0 kPa x 25.0 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 300 K
n = 3.01 mol
number of mols of gas - 3.01 mol
Explanation:
The given reaction equation will be as follows.

Now, number of atoms on reactant side are as follows.
Number of atoms on product side are as follows.
Therefore, this equation is balanced since atoms on both reactant and product sides are equal.
Thus, we can conclude that there is one sulfur atom in the products.
we are given
a swimming pool contains 2,850 kiloliters (kL) of water
2,850 kiloliters (kL)=2850000L
we know that


Firstly , we will find for 1L

now, we can multiply both sides by 2850000



so,
a swimming pool contains 752972.25892gal of water...........Answer
When we can get Pka for K2HPO4 =6.86 so we can determine the Ka :
when Pka = - ㏒ Ka
6.86 = -㏒ Ka
∴Ka = 1.38 x 10^-7
by using ICE table:
H2PO4- → H+ + HPO4
initial 0.4 m 0 0
change -X +X +X
Equ (0.4-X) X X
when Ka = [H+][HPO4] / [H2PO4-]
by substitution:
1.38 X 10^-7 = X^2 / (0.4-X) by solving for X
∴X = 2.3x 10^-4
∴[H+] = X = 2.3 x 10^-4
∴PH = -㏒[H+]
= -㏒ (2.3 x 10^-4)
∴PH = 3.6