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Dispose of lab waste properly
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When light travels from air into water,it slows down,causing it to change directions slightly
Answer:
3853 g
Step-by-step explanation:
M_r: 107.87
16Ag + S₈ ⟶ 8Ag₂S; ΔH°f = -31.8 kJ·mol⁻¹
1. Calculate the moles of Ag₂S
Moles of Ag₂S = 567.9 kJ × 1 mol Ag₂S/31.8kJ = 17.858 mol Ag₂S
2. Calculate the moles of Ag
Moles of Ag = 17.86 mol Ag₂S × (16 mol Ag/8 mol Ag₂S) = 35.717 mol Ag
3. Calculate the mass of Ag
Mass of g = 35.717 mol Ag × (107.87 g Ag/1 mol Ag) = 3853 g Ag
You must react 3853 g of Ag to produce 567.9 kJ of heat
Answer:
20 amu
Explanation:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
Atomic mass = Number of protons + number of neutrons
Atomic number = Number of electrons or number of protons.
In given question it is stated that atom has 11 electrons and -1 charge it means this atom has 12 electrons in neutral state.
Thus it has 12 protons because number of electrons and protons are always equal.
Atomic mass of given atom:
Atomic mass = Number of protons + number of neutrons
Atomic mass = 12 + 8 = 20 amu
1.Start with the number of grams of each element, given in the problem.
2.Convert the mass of each element to moles using the molar mass from the periodic table.
3.Divide each mole value by the smallest number of moles calculated.
4.Round to the nearest whole number. This is the mole ratio of the elements and is.
