A hydrogen atom is an atom of the chemical element hydrogen. The electrically neutral atom contains a single positively charged proton and a single negatively charged electron bound to the nucleus by the Coulomb force. Atomic hydrogen constitutes about 75% of the baryonic mass of the universe.
Density = (mass) / (volume)
Density = (17.0 g) / (25.3 cm³) = 0.672 gm per cm³. (rounded)
Answer:
mass PbI₂ formed = 1383 grams
Explanation:
Pb(NO₃)₂ + 2NaI => 2NaNO₃ + PbI₂(s)
6 mol NaI => 1/2(6 mol) PbI₂ = 3 mol PbI₂ x 461.01 g/mol = 1383.03 grams ≅ 1383 grams (4 sig. figs.)
Answer:
b. 3.66x10²³ atoms of chromium.
Explanation:
First we calculate how many moles are there in 31 grams of chromium, using its molar mass:
- Molar Mass of Chromium = 51 g/mol (This can be found on any periodic table)
- 31 g ÷ 51 g/mol = 0.608 mol
Then we <u>calculate how many atoms are there in 0.608 moles</u>, using <em>Avogadro's number</em>:
- 0.608 mol * 6.023x10²³ atoms/mol = 3.66x10²³ atoms
The correct answer is thus option b. 3.66x10²³ atoms of chromium.
Answer:
Every atom has no overall charge (neutral). This is because they contain equal numbers of positive protons and negative electrons. These opposite charges cancel each other out making the atom neutral.
Explanation: