C. both a and b
If a light bulb can last longer with the same amount of energy it is given, that means it can use less energy to do the same job compared to one that does not last longer with the same amount of energy it is given. It is much like how a more fuel efficient car will be able to go farther on the same tank of gas, but if you pair it with a car that doesn't have as great of an mpg, when they go the same distance, the car with the greater mpg spends less fuel.
If you don't have to use the energy when you aren't utilizing it, then you can conserve the energy for when you do need it.
Answer:The distribution of electrons in an atom is called as Electronic Configuration. Formula 2n2 helps in the determination of the maximum number of electrons present in an orbit, here n= orbit number.
Explanation:
Answer:
it's lead (ii) nitrate the name
Answer:
m = 65.637 g
Explanation:
Heat = 0.612 kJ = 612 J ( Converting to J by multiplying by 1000)
Initial Temperature = 30.°C
Final Temperature = 51°C
Temperature change = Final Temperature - Initial Temperature = 51 - 30 = 21°C
Mass = ?
The relationship between these quantities is given by the equation;
H = mCΔT
where c = 0.444 J/g°C
Inserting the values in the equation;
612 = m * 0.444 * 21
m = 612 / (0.444 * 21)
m = 65.637 g
Answer:
C. 
Explanation:
Molecules with the stronger intermolecular forces are pulled tightly together to form solid at higher temperatures and that's why the freezing point is higher.
Also, molecules with the stronger intermolecular force have greater interaction between the molecules and thus on heating do not boil easily and have high boiling point also.
Thus, melting point and boiling point increases with increase in number of carbon atoms and also increase in intermolecular forces (like hydrogen bonding, if present).
Thus, the compound which is gas at room temperature is <u>because it has least number of carbon atoms and absence of hydrogen bonding.</u>
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