Any chemical reaction in which the oxidation number of an atom,molecule,or ion changes by gaining or losing an electron
Answer:
The answer to your question is: letter C) 5730
Explanation:
Data
Originally Carbon - 14 254 g
Currently Carbon - 14 127 g
Half-life of Carbon -14 is when half of the original amount of Carbon disintegrates.
Then, if originally there were 254 and now there are 127, only one half life passed.
Half life of carbon -14 is 5730 years old.
Answer:
The answer to your question is 280 g of Mg(NO₃)₂
Explanation:
Data
Efficiency = 30.80 %
Mg(NO₃)₂ = ?
Magnesium = 147.4 g
Copper (II) nitrate = excess
Balanced Reaction
Mg + Cu(NO₃)₂ ⇒ Mg(NO₃)₂ + Cu
Reactants Elements Products
1 Mg 1
1 Cu 1
2 N 2
6 O 6
Process
1.- Calculate the theoretical yield
Molecular weight Mg = 24
Molecular weight Mg(NO₃)₂ = 24 + (14 x 2) + (16 x 6)
= 24 + 28 + 96
= 148 g
24 g of Mg -------------------- 148 g of Mg(NO₃)₂
147.4 g of Mg ------------------- x
x = (147.4 x 148) / 24
x = 908.96 g of Mg(NO₃)₂
2.- Calculate the Actual yield
yield percent = 
Solve for actual yield
Actual yield = Yield percent x Theoretical yield
Substitution
Actual yield =
x 908.96
Actual yield = 279.95 ≈ 280g
Answer:
20 g of CO₂ have 5.47x10²³ oxygen atoms
Explanation:
1 mol of CO₂ has 1 mol of C and 2 moles of O.
Mass / Molar mass = Moles
20 g / 44 g/m = 0.454 moles
In 1 mol we find 2 moles of O
In 0.454 moles of CO₂, we will find ( 0.454 .2) = 0.909 moles
1 mol has _____ 6.02x10²³ atoms
0.909 moles have (0.909 . 6.02x10²³) = 5.47x10²³ atoms
Answer:
Anaesthesia & Intensive Care Medicine
Volume 6, Issue 9, 1 September 2005, Page 294
Force, mass and acceleration
Author links open overlay panelPhilDalrympleaRichardGriffithsb
https://doi.org/10.1383/anes.2005.6.9.294
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Abstract
Force, mass and acceleration are everyday words but often used inaccurately. Force is a physical influence, which when applied to an object causes it to accelerate in the direction from which it was applied. Mass is the amount of matter in an object and is expressed in kilograms. Acceleration is the rate of change of velocity of an object in the same straight line of the unbalanced force. When forces become balanced, there is no net force and therefore no movement. Newton’s second law links these three terms and concerns the effect that an unbalanced force has on the motion of an object. It states that the rate of change of velocity of an object is directly proportional to the force applied and takes place in the direction of the force. It is summarized by the equation: Force (N) = mass (kg) × acceleration (m/s2). Thus, an object of constant mass accelerates in proportion to the force applied. Gravity is the variable force of attraction between any two objects. All matter possesses gravitational ‘pull’ towards other matter. The amount of gravity between two objects is dependent on their mass and the distance between their centres. The word ‘weight’ in its proper context refers to the downward vertical force exerted on an object as a result of the earth’s gravity. An object with greater mass is therefore subjected to a greater gravitational force (i.e. it has greater weight).