False, The human body is mostly water, so the most common element is either hydrogen or oxygen.
Answer: C. iron oxide
Explanation:
In a chemical reaction , the reactants are written on the left hand side followed by a rightarrow and then products are given on the right side of the arrow.
In the given chemical equation :
Reactants are iron (Fe) and oxygen 
and product is iron oxide 
.
As size increases<span> or decreases, </span>DENSITY REMAINS THE SAME<span>! As a rule, things that are MORE dense will sink or fall to the bottom of things that are LESS dense (think of oil and water). ... Notice that </span>if<span> you DECREASE the </span>mass<span> of something or</span>INCREASE<span> the </span>volume<span>, the </span>density<span> will be less…</span>
Answer:
A. 0.295 mole
B. 0.055 mole
C.0.144 mole
D. 0.03 mole
Explanation:
To find the amount in moles, we simply use a mathematical relation that connects mass, atomic mass and number of moles.
Number of moles = mass/atomic mass
A. Atomic mass of Argon is 40
n = 11.8/40 = 0.295 mole
B. Atomic mass of zinc is 65
n = 3.55/65 = 0.055 mole
C. Atomic mass of Tantalum is 181
n = 26.1/181 = 0.144 mole
D. Atomic mass of lithium is 7
n = 0.211/7 = 0.03 mole
