<span>The answer is "D" where the number of collisions per unit area is reduced by one-half. Drawing back on the piston means the volume is increased. The pressure is reduced. There are fewer collisions when the pressure is reduced.</span>
Grinding pepper. It is still pepper.
I hope this helps!
The grams of Mg(OH)2 produced is calculated as below
calculate the moles of HCl produced =molarity xvolume/1000
= 0.3 x 435/1000= 0.1305 moles
write the equation for reaction
Mg(OH)2 +2HCl = MgCl2 + 2H2O
by use of mole ratio between HCl :MgCl2 which is 2 :1 the moles of HCl = 0.1305 x1/2 =0.0653 moles of MgCl2
mass of MgCl2 = moles x molar mass
= 0.0653mol x95 g/mol = 6.204 grams of MgCl2
There are 20.8 moles of propanol
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
1.2 x 10⁵ molecules of propanol

Answer:
In direct observation, EVERY INDIVIDUAL in a population is counted. In indirect observation, SIGNS OF AN INDIVIDUAL, such as tracks or nests, are counted.
Explanation:
Direct observation is to involve looking at the actual behavior or occurrence so for your question it would be every individual.
Indirect observation is a result of that occurrence, so for your question it would be the signs of an individual.