Answer: caffeine is a compound.
Explanation:
1) As stated c<span>affeine contains hydrogen, carbon, nitrogen, and oxygen atoms in a fixed ratio.
2) The definition of compound is a pure substance formed by chemical bonding of two or more fifferent elements. That means a defined ratio of the elements in the compound, which conferes uniform and equal properties to every part of the compound.
Some examples of compounds are salt (NaCl), water (H2O), vinegard (CH3 COOH).
A mixture combines several elements or compounds, not bonded by chemical bonds but mixed in ratios which may vary.
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This one is easy. It's just addition and subtraction. Add the partial pressure of Argon and the partial pressure of Helium:
152 kPa
<u>+305 kPa</u><u>
</u> 457 kPa
Next, subtract the result from the total pressure:
1015 kPa
<u>- 457 kPa</u>
558 kPa
Answer:
pH 
Explanation:
For every mole of hydrochloric acid, one mole of hydronium ion is required. Thus, in order to neutralize 0.014 moles of HCL, 0.014 moles of hydronium is required.
![[H_3O^+] = [HCl] = 0.014](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%20%3D%20%5BHCl%5D%20%3D%200.014)
pH ![= -log [H^+] = -log [H_3O^+]](https://tex.z-dn.net/?f=%3D%20-log%20%5BH%5E%2B%5D%20%3D%20-log%20%5BH_3O%5E%2B%5D)
Substituting the available values in above equation, we can say that the pH of the solution is equal to
pH
pH of a 
M HCL solution
Answer:
19.39mph
Explanation:
To calculate speed, the formula; distance (d)/time(t) is used.
In this question, a distance of 40yards and a time of 4.22seconds is given. We need to convert the distance to miles and time to hours.
If 3600s = 1 hr
Then 4.22s will be 4.22/3600 hours
= 0.001172hours.
If 1760 yd = 1 mile
Then 40 yd will be 40/1760 miles
= 0.02272miles
Hence, the speed in miles per hour (mph) = 0.02272miles ÷ 0.001172hours
= 0.02272 ÷ 0.001172
= 19.38566
= 19.39
Therefore, the speed of the player is 19.39 miles per hour (mph).
Red blood cells. Need glucose oxygen to convert to carbon dioxide
