Answer:
D: to transport materials through the body.
Explanation:
A: to bring oxygen into the lung. is incorrect because it's respiratory system
B: to put carbon dioxide into all the blood vessels carbon dioxide is exhaled out of the body
C: to expel waste products from the body. is excretory system
In preparing diluted solutions from concentrated solutions we can use the following formula
c1v1 = c2v2
c1 and v1 are the concentration and volume of the concentrated solution respectively
c2 and v2 are the concentrations and volume of the diluted solution respectively
Substituting these values ,
20 mL x 1.0 M = C x 60 mL
C = 0.33 M
The concentration of the resulting diluted solutions is 0.33 M
In thermal cracking, high temperatures (typically in the range of 450°C to 750°C) and pressures (up to about 70 atmospheres) are used to break the large hydrocarbons into smaller ones. Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds - alkenes.
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
Answer:
Explanation:
Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms to gain more stability, which is gained by forming a full electron shell. By sharing their outermost (valence) electrons, atoms can fill up their outer electron shell and gain stability.
