Answer:
Explanation:
Greetings,
According to the provided chemical equation, the production of 31.2 mL of hydrogen allows one to calculate its moles using the ideal gas equation as detailed below:
Since the ratio of hydrogen to magnesium is 1:1, its milligrams are derived through the following proportional factor calculation:
Regards.
Ca3(PO4)2 is the correct formula.
145 hours.
Explanation: Riding a bicycle for one hour expends 505 kcal of energy. Given that one gram of body fat equals 7.70 kcal, and 1 pound of body fat is equivalent to 454 grams:
1 lb = 454 g; thus, 21 lb = 21 × 454/1 = 9534 g. Moreover, converting 9534 g of body fat gives us 9534 × 7.70 kcal/1 = 73411.8 kcal. If riding for one hour burns 505 kcal, then to lose 73411.8 kcal, it would require 73411.8 kcal x 1 hour/505 kcal = 145 hours.
(c) Cu + S → CuS is classified as a redox reaction
Explanation:
The following reactions are presented:
(a) K₂CrO₄ + BaCl₂ → BaCrO₄ + 2 KCl
(b) Pb²⁺ + 2 Br⁻ → PbBr₂
(c) Cu + S → CuS
Reaction (c) represents a redox reaction, as the oxidation states of the elements are changing. In this case:
Cu + S → CuS
In its elemental form, Cu has an oxidation state of 0, while in CuS (copper sulfide), its oxidation state changes to +2.
Similarly, S in its elemental form has an oxidation state of 0 and is -2 in CuS (copper sulfide).
Learn more about:
redox reactions
The empirical formula is K₂CO₃.
This formula represents the most simplified whole-number ratio of atoms in a chemical compound.
The atom ratio aligns with the mole ratio, which means our task is to find the molar ratios for K:C:O.
I prefer to summarize these calculations in table form.
Element Moles Ratio¹ Integers²
K 0.104 2.00 2
C 0.052 1.00 1
O 0.156 3.00 3
¹ To obtain the molar ratio, each mole value is divided by the smallest mole count.
² Convert the ratio values to integers (2, 1, and 3).
The empirical formula is K₂CO₃.
