Considering the definition of calorimetry and sensible heat, the change in temperature if the gold releases 0.106 kJ of heat as it cools is 28.78°C.
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is the amount of heat that a body absorbs or releases without any changes in its physical state (phase change). It is calculated by the expression:
Q = c× m× ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case, you know:
- Q= 0.106 kJ= 106 J (being 1 kJ=1000 J)
- c= 25.4
- m= 28.5 g×
= 0.145 moles (being 196.967 g/mole the molar mass of gold) - ΔT= ?
Replacing:
106 J= 25.4 × 0.145 moles× ΔT
Solving:
ΔT=
ΔT= 28.78 C
The change in temperature if the gold releases 0.106 kJ of heat as it cools is 28.78°C.
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In order to answer this, we mus know the data for the heat of combustion of propane. This is an empirical data that you can search online. The heat of combustion is -2220 kJ/mol. The molar mass of propane of 44.1 g/mol. The solution is as follows:
ΔH = -2220 kJ/mol (1 mol/44.1 g)(1000g/1kg)(20 kg)
<em>ΔH = -1006802.721 kJ or -1 GJ</em>
Answer:
The correct option is: 2.50 g
Explanation:
Reaction involved: Mg(s) + 2 HCl(aq) → MgCl₂(aq) + H₂(g)
Molar mass: Mg = 24.305 g/mol, HCl = 36.461 g/mol
In the given reaction, 1 mole Mg reacts with 2 moles HCl.
Given: mass of HCl = 7.50 g
So, the number of moles of HCl = given mass ÷ molar mass = 7.50 g ÷ 36.461 g/mol = 0.2057 moles
Therefore, the<u> number of moles of Mg</u> that reacts with 0.2057 mole HCl = 0.2057 ÷ 2 = 0.1028 moles
Therefore, <u>the mass of Mg in grams</u> = molar mass × number of moles = 24.305 g/mol × 0.1028 mole = 2.5 g
The ground water refers to water present in the under earth in the cracks or pores or similar spaces.We majorly depends upon this sources of water specially in rural area.
It helps in irrigation and also serve as drinking water supply.
The words or phrases which identify layer of ground water are:
a) water table: the uppermost water saturated layer
b) kettle lake: it is an underground lake (not ground water)
c) Saturation zone : this is the zone of water below the water table
d) undergound lake: this is kettle lake (not ground water)
e) sink hole: Not a layer of ground water
So the layers of ground water are
a) water table
b) saturation zone
I'm going to suppose you want the adjusted chemical reaction, using the formulas of the compounds. You can see it in the image attached.
