ANSWER : 108 + 10 = 118
118 + ( 5 + 3 )
118 + 8 = <u>1</u><u>2</u><u>6</u>
<u>=</u><u> </u><u>1</u><u>2</u><u>6</u><u> </u><u>g</u>
The particles in a solid are tightly packed and locked in place. Although we cannot see it or feel it, the particles are vibrating in place.
As these molecules heat up, they will vibrate more vigorously, and will eventually turn to water, then gas.
T=20 min
m₀=200 g
t=60 min
the mass of element through time t is:
m=m₀*2^(-t/T)
m=200*2^(-60/20)=25 g
25 grams of element will be left after 60 minutes
I believe the correct answer is C, but I'm 100% on this. Hope this helped though!
-TTL
The molecular weight of water is <span>18.01528 g/mol.
So in 2.92 grams there are 2.92/</span>18.01528 = 0.1621 mol of particles.
1 mol contains 6,02214 × 10^<span>23 particles by definition.
So the nr of H2O molecules is </span>0.1621 * 6,02214 × 10^23 = 0,9761 × 10^23.
Every molecule has 2 H atoms, so you have to double that.
2* 0,9761 × 10^23 = 1.952 × 10^23.