It glow, so light energy go out of the system, exotermic
Answer : The final temperature of the mixture is 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.


And as we know that,
Mass = Density × Volume
Thus, the formula becomes,

where,
= specific heat of ethanol = 
= specific heat of water = 
= mass of ethanol
= mass of water
= density of ethanol = 0.789 g/mL
= density of water = 1.0 g/mL
= volume of ethanol = 45.0 mL
= volume of water = 45.0 mL
= final temperature of mixture = ?
= initial temperature of ethanol = 
= initial temperature of water = 
Now put all the given values in the above formula, we get


Therefore, the final temperature of the mixture is 
For mild to moderate reactions, treatment involves removing the stinger, washing the area with soap and water, and applying cold compresses or ice. Creams to the affected area can help reduce discomfort. Severe reactions may need epinephrine.
Answer:
A) 14. 25 × 10²³ Carbon atoms
B) 34.72 grams
Explanation:
1 molecule of Propane has 3 atoms of Carbon and 8 atoms of Hydrogen.
The sample has 3.84 × 10²⁴ H atoms.
If 8 atoms of Hydrogrn are present in 1 molecule of propane.
3.84 × 10²⁴ H atoms are present in

<u>= 4.75 × 10²³ molecules of Propane</u>.
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No. of Carbon atoms in 1 molecule of propane = 3
=> C atoms in 4.75× 10²³ molecules of Propane = 3 × 4.75 × 10²³
<u>= 14.25 × 10²³ </u>
<u>________________________________________</u>
<u>Gram</u><u> </u><u>Molecular</u><u> </u><u>Mass</u><u> </u><u>of</u><u> </u><u>Propane</u><u>(</u><u>C3H8</u><u>)</u>
= 3 × 12 + 8 × 1
= 36 + 8
= 44 g
1 mole of propane weighs 44g and has 6.02× 10²³ molecules of Propane.
=> 6.02 × 10²³ molecules of Propane weigh = 44 g
=> 4. 75 × 10²³ molecules of Propane weigh =



<u>= 34.72 g</u>
Dinitrogen trioxide is the compound N2O3. :)