Answer: 72 grams of 
are needed to completely burn 19.7 g 
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number 
of particles.
To calculate the number of moles, we use the equation:
Putting in the values we get:
According to stoichiometry:
1 mole of 
requires 5 moles of oxygen
0.45 moles of require= 
moles of oxygen
Mass of 
72 grams of are needed to completely burn 19.7 g
67.45 is the answer I think
Identify<span> each </span>bond<span> as either </span>polar<span> or nonpolar.</span>
Answer:
6
Explanation:
To determine the number of neutrons we round 10.8 to 11 and subtract the atomic number (5) and get 6; therefore, boron has 6 neutrons.
