Question

$calculate \: the \: number \: of \:$
$molecules \: in \: a \: drop \: of \:$
$water \: weighing \: 0.048 \: g$
Concept : Mole
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Answer 1

Answer:

nervous system can be defined as an organized group of cells, called neurons, specialized for the conduction of an impulse—an excited state—from a sensory receptor through a nerve network to an effector, the site at which the response occurs.

Answer 2

Answer:

• 1.606 × 10²¹ molecules.

Explanation:

We know:

$\bold{H_{2}O\;weight\;=2(1)+16=18g.}$

$\bold{18 g \;of \;H_{2}O\;contains\;6.022\times10^{23}\;molecules.}$

To find:

$\bold{Number\;of\;molecules\;in\;0.048g\;of\;H_{2}O.}$

Solution:

$\bold{18g\;-\;6.022 \times 10^{23} \; molecules.}$

$\bold{0.048g \;-\;?\;molecules.}$

• 18x = 6.022 × 10²³ × 0.048
• x = 6.022 × 10²³ × 0.048/18
• x = 0.289104 × 10²³/18
• x = 0.01606 × 10²³
• x = 1.606 × 10²¹

∴ There are 1.606 × 10²¹ molecules in one drop of water weighing 0.048 g.