<u>Answer:</u>
<em>Atomic number 75 is dedicated to an element named rhenium and has been given Re as its chemical name.</em>
<u>Explanation:</u>
With a really low concentration it is one of the rarest metals that is found in Earth's crust.
Like all other elements rhenium also has certain isotopes among with 185 and 187 are the most stable ones. Hence these two are the ones that are naturally available abundance is 34% and 63% respectively.
Answer:
Growth of weeds and grasses
Explanation:
The part of the garden, probably left to rest by the Gardner, would start experiencing a legion of invasive plants. Giant weeds and grasses could be seen, and brambles and tree seedlings could also sneak in.
Some Gardeners would recommend the use of herbicides to restore order to an abandoned garden even though certain scientists are of the opinion that chemicals may not offer a sound solution to the problem.
Using the Rydberg formula, the spectral line of H - atom is suitable for this purpose is Paschen, ∞ → 3.
- Using the Rydberg formula;
1/λ = RH(1/nf^2 - 1/ni^2)
Given that;
λ = wavelength
RH = Rydberg constant
nf = final state
ni = initial state
- When final state = 3 and initial state = ∞
Then;
1/λ = 1 × 10^7 m-1 (1/3^2 - 1/ ∞^2)
1/λ = 1 × 10^7 m-1 (1/3^2 )
λ = 900 nm
Hence, the correct answer is Paschen, ∞ → 3
Learn more about the Rydberg formula; brainly.com/question/17753747
When you want to melt an ice, you only need the latent energy of fusion, <span>δhfus. We use the given value, then multiply this with the given amount to determine the amount of energy. Since the energy is per mole basis, use the molar mass of ice which is 18 g/mol. The solution is as follows:
</span>ΔH = 5.96 kJ/mol * 1 mol/18 g * 500 g
<em>ΔH = 165.56 kJ</em><span>
</span>
For 23., you have to find a way to measure your heart rate not increase it. search it up on google.
