The energy required to heat 40g of water from -7 c to 108 c is
1541000 joules
calculation
Q(heat)= M( mass) x c(specific heat capacity) xdelta t( change in temperature)
M= 40g= 40/1000= 0.04 Kg
C= 335,000 j/kg/c
delta T ( 108 --7= 115 c)
Q is therefore = 0.04 g x 335000 j/kg/c x 115 c = 1541,000 joules
<span>34.2 grams
Lookup the atomic weights of the involved elements
Atomic weight potassium = 39.0983
Atomic weight Chlorine = 35.453
Atomic weight Oxygen = 15.999
Molar mass KClO3 = 39.0983 + 35.453 + 3 * 15.999 = 122.5483 g/mol
Moles KClO3 = 87.4 g / 122.5483 g/mol = 0.713188188 mol
The balanced equation for heating KClO3 is
2 KClO3 = 2 KCl + 3 O2
So 2 moles of KClO3 will break down into 3 moles of oxygen molecules.
0.713188188 mol / 2 * 3 = 1.069782282 mols
So we're going to get 1.069782282 moles of oxygen molecules. Since each molecule has 2 atoms, the mass will be
1.069782282 * 2 * 15.999 = 34.23089345 grams
Rounding the results to 3 significant figures gives 34.2 grams</span>
Answer:
1. 7.256g of NaCl
2. 47.33g of Cl2
Explanation:
2 moles of Na reacts to produce 2 moles of NaCl
8 moles of Na will still produce 8 moles of NaCl
Mass of NaCl = molar mass of Nacl/moles of Nacl
=58.5/8
=7.256g of NaCl
From the equation, 2 moles of Na reacts with 1 mole of Cl2
3/2 moles of Cl2 will react with 3 moles of Na
Mass of Cl2 = 71/1.5
=47.33g of Cl2
Answer:
Explanation:
In this case, we have a dilution problem. We have to remember that in the dilution procedure we go from a solution with higher concentration to a solution with lesser concentration. Therefore we have to start with the dilution equation:
Now we can identify the variables:
If we plug all the values into the equation:
And we solve for 
:
I hope it helps!
When solid carbon reacts with oxygen gas to produce carbon dioxide gas. the deltaH (enthalpy change ) value is negative .DeltaH would be on the product side of the equation.
<h3>What is enthalpy change? </h3>
In a thermodynamic system, energy is measured by enthalpy. Enthalpy is a measure of a system's overall heat content and is equal to the system's internal energy plus the sum of its volume and pressure.
Knowing whether q is endothermic or exothermic allows one to characterise the relationship between q and H. An endothermic reaction is one that absorbs heat and demonstrates that heat from the environment is used in the reaction, hence q>0 (positive). For the aforementioned equation, under constant pressure and temperature, if q is positive, then H will also be positive. In a similar manner, heat is transferred to the environment when it is released during an exothermic reaction. Thus, q=0 (negative). Therefore, if q is negative, H will also be negative.
Learn more about enthalpy change here :
brainly.com/question/1445358
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