Answer:
It’s true ( pure).
Explanation:
An element is defined as a pure substance that is not chemically combined with any other elements. An element comprises of mainly the sane type of atoms.
While a compound is a substance that consists of two or more elements which are chemically combined together. This is the main difference between an element and a compound.
Answer:
59.92 × 10²³ atoms are in 9.95 moles of iron
1.8 ×10²² molecules are in 0.03 moles of Carbon dioxide
1.19 moles are found in 7.20 x 10^23 atoms of platinum
Answer:
1) The elements have filled valence levels.
Explanation:
Since they have filled valence levels, they're stable and don't need to electrons to fill their valence shells since they're already full.
2) False, They do have electrons
3) False, He does have only one electron shell, but going down the periods, every next element have one more electron shell than a preceding one has.
4)False, they're actually the smallest atoms of their respective period
The number of C2H5OH in a 3 m solution that contain 4.00kg H2O is calculate as below
M = moles of the solute/Kg of water
that is 3M = moles of solute/ 4 Kg
multiply both side by 4
moles of the solute is therefore = 12 moles
by use of Avogadro law constant
1 mole =6.02 x10^23 molecules
what about 12 moles
=12 moles/1 moles x 6.02 x10^23 = 7.224 x10^24 molecules
Answer:
they are equal.
Explanation:
1 mol = 6.022 × 10^23 (Avogadro's constant), which is the number of atoms in 1 mol of any element. Doesn't matter what their atomic mass is, although, of course, 1 mol of carbon weighs less than 1 mol of calcium, but its because their mass is different, but the point is, in 1 mol of any element there is 6.03*10^23 atoms
This is like saying, what weighs more, 10 kg of feathers or 10 kg of metal