69.9%
Explanation:
To find the mass percentage of iron in the compound in Fe₂O₃, we would go ahead to express the given molar mass of the iron to that of the compound.
Mass percentage = 
x 100
Molar mass of Fe = 55.85g/mol
Molar mass of O = 16g/mol
Molar mass of Fe₂O₃ = 2(55.85) + 3(16) = 159.7g/mol
Mass percentage = 
= 69.94% = 69.9%
learn more:
Mass percentage brainly.com/question/8170905
#learnwithBrainly
The answer is the reaction ins a cold pack
Answer is: the atom is the smallest known particle of matter.
John Dalton claimed that atom is indestructible and a<span>ll atoms of a given element are identical in mass and properties.
</span>Thomson discovered electron and found the first evidence for isotopes<span> of a stable element.</span>
Answer:
1.8 × 10² s
Explanation:
Let's consider the reduction that occurs upon the electroplating of copper.
Cu²⁺(aq) + 2 e⁻ ⇒ Cu(s)
We will establish the following relationships:
- 1 g = 1,000 mg
- The molar mass of Cu is 63.55 g/mol
- When 1 mole of Cu is deposited, 2 moles of electrons circulate.
- The charge of 1 mole of electrons is 96,486 C (Faraday's constant).
- 1 A = 1 C/s
The time that it would take for 336 mg of copper to be plated at a current of 5.6 A is:
Answer:
= 3132.9 Joules
Explanation:
- Kinetic energy is the energy possessed by a body when in motion.
- Kinetic energy is calculated by the formula; K.E = 1/2 mV², where m is the mass of the body or object, and V is the velocity.
- Therefore kinetic energy depends on the mass and the velocity of the body or the object in motion.
In this case;
Kinetic energy = 0.5 × 0.018 kg × 590²
<u>= 3132.9 Joules</u>
