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
Answer:
i think so
Ba(OH)2 + H2SO4 ------> BaSO4 + 2H2O
1) Moles of Ba(OH)2 = moles of H2SO4 = 0.025L x 2)0.02M = 5.0 x 10^-4M
Concn of Ba(OH)2 in g/L = 5.0 x 10^-4M x 171.33g/mol = 0.086g/mol
The words aa q.s. is an abbreviation which is used in
pharmacy. This is usually written by prescribers and then translated by
pharmacists. The aa is derived from Latin which means “of each” while q.s. is
also derived from Latin which means “a sufficient quantity”. This simply means
that there is equal amount of Hytone 1% cream and Lotrimin 1% cream in the
total cream formulation.
Since we are to make a total of 60 g of cream, therefore
50% of it would be Lotrimin cream.
Amount of Lotrimin cream needed = 0.5 (60 g)
<span>Amount of Lotrimin cream needed = 30 grams</span>
Answer:
Neutral
Explanation:
Atoms on the periodic table all have neutral electric charges. This is because they have an equal number of protons, which are positivly charged, and electrons, which are negatively charged.
In chemistry, there are two types of change, they are chemical and physical changes. A chemical change is one in which new substance are formed and it is always irreversible while a physical change is one in which no new substance is formed and it is always reversible. There are many factors that can indicate that a chemical change has taken place, these include: energy transfer, formation of precipitation, gas production, etc. Fracture formation does not indicate chemical change. In fracture formation nothing changes, so it is a form of physical change.
