Answer:2
Explanation:
Ba(OH)2 contains two oxygen atoms
BaSO4 contains four oxygen atoms.
This means that barium sulphate contains two more oxygen atoms than barium hydroxide in its formula. This is clearly seen from the two formulae shown above.
Tarnish is Ag2S-silver sulfide and the oxidation state of silver is +1
Answer:
20% of phosphorus
Explanation:
A fertilizer is used to improve the fertility of soils. Most fertilizers contains the element nitrogen, phosphorus and potassium.
They are often designated NPK fertilizers.
Now we know that the numbers 10-20-20 depicts the nitrogen-phosphorus and potassium content of the fertilizer.
From the designation,
The actual percentage is 20% of phosphorus.
10% of nitrogen
20% of potassium
Answer: 3.69 × 10^27
Explanation:
Amount of energy required = 7.06 × 10^4 J
Frequency of microwave (f) = 2.88 × 10^10 s−1
Planck's constant (h) = 6.63 × 10^-34 Jᐧs/quantum
Recall ;
Energy of photon = hf
Therefore, energy of photon :
(6.63 × 10^-34)j.s× (2.88 × 10^10)s^-1
= 19.0944 × 10^(-34 + 10) = 19.0944×10^-24 J
Hence, number of quanta required :
(7.06 × 10^4)J / (19.0944 × 10^-24)J
= 0.369 × 10^(4 + 24) = 0.369×10^28
= 3.69 × 10^27
