The glow emitted by a substance exposed to external radiation is called 'fluorescence'. In fluorescence, a fluorophore is exposed to external radiation, absorbs the energy and emits a form of light or glow. The answer to this question is 'fluorescence'. I hope this helps.
<span>(1) CH3CHCHCH3.................</span>
Answer:
Explanation:
Given that,
Mass of the sample, m = 275 g
It required 10.75 kJ of heat to change its temperature from 21.2 °C to its melting temperature, 327.5 °C.
We need to find the specific heat of the metal. The heat required by a metal sample is given by :
c is specific heat of the metal
So, the specific heat of metal is 
.
Full Question:
Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. What mass of water is produced by the reaction of 7.7g of ammonia?
Be sure your answer has the correct number of significant digits.
Answer:
12.23g ≈ 12g (2 s.f)
Explanation:
Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. The balanced chemical reaction is given as:
4 NH3 + 5 O2 -------> 4 NO + 6 H2O
From the reaction;
4 mole of ammonia reacts to produce 6 moles of water
From the question;
Moles = mass / molar mass
From the question;
moles of ammonia = mass / molar mass = 7.7 / 17 = 0.4529moles
Number of moles of water produced;
4 = 6
0.4529 = x
x = (0.4529 * 6 ) / 4
x = 0.67935moles
Mass of water = moles * molar mass = 0.67935 * 18 = 12.23g ≈ 12g (2 s.f)
