The number of moles in a substance indicates the amount of the substance that contains the same number of particles as 12 g of the Carbon-12 isotope [or equivalent to 6.02 × 10²³] (which is used as a standard in the world of moles).
Now,
if 6.02 × 10²³ atoms are found in 1 mole ofsodium
then let 9.76 × 10¹² atoms are found in x
⇒ x = (9.76 × 10¹² ) ÷ (6.02 × 10²³)
= 1.619 × 10⁻¹¹ mol
Now, mass = moles × molar mass
∴ mass of Na = 1.619 × 10⁻¹¹ mol × 23 g/mol
= 3.72 × 10⁻¹⁰ g
Actually, there are four kinds of reptile motion:
Concertina - vermiform. Circular muscles around the snake squeeze the front of the snake's body out long, then the latter half is pulled forward.
Rectilinear crawling - Belly scutes are moved forward individually in a wave-like motion.
Side-winding - Snake's version of "walking". Use by several species to move over fluidic substrates, such as sand.
Lateral undulation - Most common form of movement. Snake presses on alternating pressure points to force body forward (or backward)
(taken from a user on Yahoo from Correct Answers)
7 A lead
B Gold
Csilver
8 Afeathrr
B water
C silver
Answer:
refer the above attachment
- According to Pascal’s principle, for a certain fluid in a totally enclosed system, a change in pressure at a given point in the fluid is transferred to all points in the fluid, as well as to the enclosing walls.
- This is illustrated by the fact that the pressure inside an enclosed system is the same according to the relation [ pressure = force/area ]. Therefore, the change in pressure resulting from squeezing a ketchup bottle will be transferred equally to all parts of that bottle as well as its internal content.
- That’s how hydraulic machines, such as garbage trucks and hydraulic lifts function..
