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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The density of the block will be "7.11 gm/cm³". A further explanation is provided below.
Given values are:
Density of iron,
Mass of block of metal,
Volume of block,
By using the formula,
→ 
then,
→ The density of block will be:
= 
= 
= 
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potassium reacts the most vigorously.
Hello
I don't quite understand the question your asking and if there is any answers provided but I will still give you mine.
Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.
Hope this helps!!
Have a nice day!!
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Answer:</u></h2>
n = 0.0989 moles
<h2><u>
Explanation:</u></h2>
n = PV / RT
P = 2.09atm
V = 1.13L
R = 0.08206
T = 291K
Plug the numbers in the equation.
n = (2.09atm)(1.13L) / (0.08206)(291K)
n = 0.0989 moles