Answer:
Hello!
Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element.
So in short, the Correct Answer will be (D) an Element.
Hope that Helps! Have A Wonderful Day! ☺
Explanation:
Answer:
The molality of the KCl solution is 11.8 molal
Explanation:
Step 1: Data given
Mol fracrion KCl = 0.175
Molar mass KCl = 74.55 g/mol
Molar mass H2O = 18.02 g/mol
Step 2: Calculate mol fraction H2O
mol fraction H2O = 1 - 0.175 = 0.825
Step 3: Calulate mass of H2O
Suppose the total moles = 1.0 mol
Mass H2O = moles H2O * molar mass
Mass H2O = 0.825 * 18.02 g/mol
Mass H2O = 14.87 grams = 0.01487 kg
Step 4: Calculate molality
Molality KCl = 0.175 / 0.01487 kg
Molality KCl = 11.8 molal
The molality of the KCl solution is 11.8 molal
Answer:
True, The Answer is true. Mechanical digestion involves physically breaking the food into smaller pieces.
Answer:
38.541 × 10¹⁹ formula units
Explanation:
Given data:
Mass of chromium sulfate = 0.25 g
Formula units in 0.25 g = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ formula units of water
Number of moles of chromium sulfate = Mass / molar mass
Number of moles of chromium sulfate = 0.25 g/ 392.16 g/ mol
Number of moles of chromium sulfate = 6.4 × 10⁻⁴ moles
Number of formula units:
1 mole = 6.022 × 10²³ formula units
6.4 × 10⁻⁴ moles × 6.022 × 10²³ formula units / 1 mol
38.541 × 10¹⁹ formula units
