Answer:
2.95 * 10^23 atoms
Explanation:
The number of atoms in a mole is always equal to <u>Avogadro's constant</u>, which is <u>6.02214076×10²³ mol⁻¹</u>.
To find the number of atoms in 0.490 moles of barium, multiply it with <u>Avogadro's constant</u>:
0.490 mol * 6.02214076×10²³ mol⁻¹ ≈ 2.9508 * 10^23
Convert to SigFigs (if necessary):
2.95 * 10^23
Answer:
B.
Butter is a mixture of pure substances.
Explanation:
just poop and you will see
As you move across a period, the atomic radii decreases. ... As you move across a period, electrons are added to the same energy level while protons are also being added. The concentration of more protons creates a higher effective nuclear charge.
1. This can be due to the dissolving of the solid in liquid and form a solution.
Dissolving is a physical property because dissolving doesn't form new substances and the chemical composition of the solid is not changed.
The color building up over the time can be due to the rate of dissolving of the solid and amount of particles have been dissolved.
Example:
- Dissolving of CuSO₄ solid in water.
- This develops a blue color.
2. This can be due to the chemical reaction between the solid and liquid.
Chemical reaction is a chemical property because from reacting substances new substances can be formed which the chemical formula is different from initial substances.
The color building up over the time can be due to the rate of the reaction and the amount of reactants.
Example:
- The reaction between calcium metal with water.
- The color of Ca(OH)₂ is white color.
- Reaction is
Ca(s) + 2H₂O(l) → Ca(OH)₂(aq) + H₂(g)
