Answer with Explanation:
A "chemical change" occurs when the structure of the molecules change. If there's no change in structure, it is called a "physical change." This also means that a <em>chemical reaction </em>has to occur for something to be considered a chemical change.
Gasoline when used as a fuel is being transformed into other forms of energy. It undergoes a process called <em>"combustion."</em>
When used as a fuel for cars, <em>the gasoline is being burned to produce </em><u><em>heat energy.</em></u> This energy is then converted into <u><em>mechanical energy</em></u> that allows the car to move. Clearly, the gasoline has undergone a chemical change.
Answer: 2) 2HCl(sq) + CaCO3(s) CaCl2(sq) + CO2(g) + H2O (l) No of moles of CaCO3 = amount of the CaCO3 (g)/mw of CaCO3 (g/mole)= 0.8085 g/100 g/mole = 0.008085
Explanation:
Answer:
The coffee has a higher temperature because a pool is so you can have fun and relax in while coffee can warm you up by drinking it.
Explanation:
Hope it helps :)
Answer:
- 178 ºC
Explanation:
The ideal gas law states that :
PV = nRT,
where P is the pressure, V is the volume, n is number of moles , R is the gas constant and T is the absolute temperature.
For the initial conditions :
P₁ V₁ = n₁ R T₁ (1)
and for the final conditions:
P₂V₂= n₂ R T₂ where n₂ = n₁/2 then P₂ V₂ = n₁/2 T₂ (2)
Assuming V₂ = V₁ and dividing (2) by Eqn (1) :
P₂ V₂ = n₁/2 R T₂ / ( n₁ R T₁) then P₂ / P₁ = 1/2 T₂ / T₁
4.10 atm / 25.7 atm = 1/2 T₂ / 298 K ⇒ T₂ = 0.16 x 298 x 2 = 95.1 K
T₂ = 95 - 273 = - 178 º C
Answer:
The correct answer is - 2770000 cm.
Explanation:
1 kilometer = 1000 meter
1 meter = 100 centimeter
1 kilometer = 100*1000 cm
1 km = 100000 cm.
then,
27.7 kilometers = 2.77 × 10^6 centimeters
So, 27.7 kilometers = 27.7 × 100000
= 2.77 × 106 or 2770000 centimeters.
