One of the amazing products that have been developed under Van Der Waals forces is the <span>suction cup</span> that is used as an ankle and is used by workers as a safety gear on cleaning or constructing high-rise buildings.
<span>Like geckos, they can scamper up walls, scuttle along ceilings and hang upside down on polished glass surfaces.</span>
142 kg in grams:
1 kg ---------- 1000 g
142 kg -------- ?
142 x 1000 / 1 => 142000 g
Atomic mass Cu = 63.54 a.m.u
Therefore:
63.54 g ------------ 6.02x10²³ atoms
142000 g --------- ??
142000 x ( 6.02x10²³) / 63.54 =
8.54.10²⁸ / 63.54 => 1.34.10²⁷ atoms of Cu
123 store stop
School and store
48
Answer:
Alexander Graham Bell
Explanation:
He created the first telephone in 1876.