Answer:
You need 375 mL of BaCl2 solution.
Explanation:
M1V1=M2V2
Dilution formula. Substitute known values and solve for V1.
M1 = 2.0 M
M2 = 1.50 M
V2 = 500 mL
(2.0 M)(V1) = (1.50 M)(500 mL)
V1 = (1.50 M)(500 mL) / (2.0 M)
V1 = 375 mL
Answer:
The nuclei of most atoms also contain neutrons . The masses of subatomic particles are very tiny. ... Since the nucleus contains protons and neutrons, most of the mass of an atom is concentrated in its nucleus. Protons and electrons have electrical charges that are equal and opposite.
The first pesticides relied on natural chemicals, such as those taken from chrysanthemum flowers is true
Answer:
The heat absorbed by the sample of water is 3,294.9 J
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
The sensible heat of a body is the amount of heat received or transferred by a body when it undergoes a temperature variation (Δt) without there being a change of physical state (solid, liquid or gaseous). Its mathematical expression is:
Q = c * m * ΔT
Where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case:
- Q=?
- m= 45 g
- c= 4.184

- ΔT= Tfinal - Tinitial= 38.5 C - 21 C= 17.5 C
Replacing:
Q= 4.184
* 45 g* 17.5 C
Solving:
Q=3,294.9 J
<u><em>The heat absorbed by the sample of water is 3,294.9 J</em></u>
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