Answer:
Explanation:
1. A measure of how quickly velocity is changing is the acceleration
Acceleration is the rate of change of velocity with time. The rate at which a body is changing its velocity is known as the acceleration.
It is measured in the unit m/s²
2. Speed in a given direction is the velocity
Velocity is a vector quantity which measures the magnitude of motion in a specific direction. It is simply speed in a given direction.
When we say a motorcycle travels at the rate of 5m/s due east, we are describing the velocity of such body.
3. Force that resists moving one object against another is the friction
Friction is a force that opposes motion. It prevents a body from moving.
4. Measure of the pull of gravity on an object Weight
Weight is a measure of the amount of gravitational force on a body. It is mathematically expressed as;
W = mg
W is the weight, m is the mass and g is the acceleration due to gravity
5 Tendency of an object to resist a change in motion is inertia
Inertia is the tendency of body to resist change in motion. It is the ability of a body to remain in a perpetual state of rest.
6 Size is the magnitude
Answer:
A) yes
B) The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Explanation:
A) I think the the Bureau of Mint changed the way it made pennies because from the experiment and observation carried out on 15 different pennies it can be seen that they had different weights and this difference is associated with the period/time of production of the different pennies,
B ) The average mass of any object should be expressed in the si unit of mass and not having ($) sign attached to the value instead it should be expressed in grams or kilograms (s.i unit of mass )
The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Answer:
C. disposition and condensation
Explanation:
Answer:
You need 8,324 g of CaCl₂ yo make this solution
Explanation:
Molarity is a way to express concentration in a solution, in units of moles of solute per liter of solution.
To know the grams of CaCl₂ it is necessary to know, first, the moles of this substance with the desired volume and concentration , thus:
0,1500 L × = 0,075 CaCl₂ moles
Now, with the molar mass of CaCl₂ you will obtain the necessary grams, thus:
0,075 CaCl₂ moles × = 8,324 g of CaCl₂
So, you need <em>8,324 g of CaCl₂</em> to make 150,0 mL of a 0,500M solution
I hope it helps!
Answer:
ΔH = +155.6 kJ
Explanation:
The Hess' Law states that the enthalpy of the overall reaction is the sum of the enthalpy of the step reactions. To do the addition of the reaction, we first must reorganize them, to disappear with the intermediaries (substances that are not presented in the overall reaction).
If the reaction is inverted, the signal of the enthalpy changes, and if its multiplied by a constant, the enthalpy must be multiplied by the same constant. Thus:
N₂(g) + O₂(g) → 2NO(g) ΔH = +180.7 kJ
2NO(g) + O₂(g) → 2NO₂(g) ΔH = -113.1 kJ
2N₂O(g) → 2N₂(g) + O₂(g) ΔH = -163.2 kJ
The intermediares are N₂ and O₂, thus, reorganizing the reactions:
N₂(g) + O₂(g) → 2NO(g) ΔH = +180.7 kJ
NO₂(g) → NO(g) + (1/2)O₂(g) ΔH = +56.55 kJ (inverted and multiplied by 1/2)
N₂O(g) → N₂(g) + (1/2)O₂(g) ΔH = -81.6 kJ (multiplied by 1/2)
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N₂O(g) + NO₂(g) → 3NO(g)
ΔH = +180.7 + 56.55 - 81.6
ΔH = +155.6 kJ