A chemical change or reaction between elements or compounds may occur when there is enough energy present. This can be in the form of heat, light, or electricity. An example of this is the reaction between hydrogen and oxygen to form water, which requires a spark.
If two or more elements or chemical compounds come into contact with one another and there is enough energy present, a chemical change may take place. This is because a chemical reaction, which represents a chemical change, requires energy to break the bonds of the reactants and form new bonds in the products. This energy can be in various forms such as heat, light, or electricity.
For example, the reaction between hydrogen and oxygen to form water is a chemical change that requires energy in the form of a spark. On the other hand, an exothermic reaction, such as the combustion of gasoline, releases energy in the form of heat and light.
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Answer:
energy
Explanation:
"If two or more elements or chemical compounds come into contact with one another and there is enough energy present, a chemical change may take place." this was on a science lesson, it's correct.
Answer:
Henderson Hasselbalch equation: pH = pKa + log [salt]/[acid]
You need to know the pKa for acetic acid. Looking it up one finds it to be 4.76
(a). pH = 4.76 + log [0.13]/[0.10]
= 4.76 + 0.11
= 4.87
(b) KOH + CH3COOH =>H2O + CH3COOK so (acid)goes down and (salt)goes up. Assuming no change in volume, you have 0.10 mol acid - 0.02 mol = 0.08 mol acid and 0.13 mol salt + 0.02 mol = 0.15 mol salt
pH = 4.76 + log [0.15]/[0.08]
= 4.76 + 0.27
= 5.03
The pH of the buffer with 0.11 mol acetic acid and 0.13 mol sodium acetate in 1.00 L is 4.91, calculated using the Henderson-Hasselbalch equation. The second part of the question regarding the pH change after the addition of '2' is unanswerable without further information on what is being added.
To answer the question of what the pH of the buffer solution containing 0.11 mol of acetic acid and 0.13 mol of sodium acetate in 1.00 L is, we can apply the Henderson-Hasselbalch equation:
pH = pKa + log([A-]/[HA])
Where [A-] is the concentration of the acetate ion and [HA] is the concentration of acetic acid. For acetic acid, the pKa is approximately 4.76. Since we have 0.11 mol of acetic acid and 0.13 mol of sodium acetate in 1.00 L solution, the concentrations are 0.11 M and 0.13 M respectively.
Substituting these values into the Henderson-Hasselbalch equation gives:
pH = 4.76 + log(0.13/0.11)
Calculating the log(0.13/0.11) yields approximately 0.15. Therefore:
pH = 4.76 + 0.15 = 4.91
The question "What is the pH of the buffer after the addition of 2?" seems to be incomplete, as it does not specify what '2' refers to. If '2' refers to adding 2 moles of a strong acid or base, for instance, the pH would change significantly and the buffer capacity might be exceeded. The exact effect on pH would depend on the nature of the substance added (acid or base) and its quantity. Without specifics, this part of the question cannot be accurately answered.
The concept of buffer capacity is relevant to discuss here. Buffer capacity refers to the amount of acid or base a buffer can absorb without a significant change in pH. Buffer solutions with higher molar concentrations of both the acid and the corresponding salt will have greater buffer capacity.
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Answer:
53.1 mL NaOH
Explanation:
Answer: The agents of soil erosion are the same as of other types of erosion for example water, ice, wind, and gravity. Soil erosion is more likely where the ground has been disturbed by agriculture, grazing animals, logging, mining, construction, and recreational activities.Basically what I mean is some causes of solid loss is mining, construction
Answer:
Mass of CO2 produced = 944.43 -lb/year
Since 944.43 -lb is close to 1000 -lb, it is a reasonable statement.
Explanation:
Assumptions:
Car mileage = 20 miles/gallon:
Density of gasoline = 0.702 g/ml
Volume of gallons per week = (20 miles/week) / (20 miles/gallon) = 1 gallon/week
Volume of gasoline per year = 52 weeks * 1 gallon/week = 52 gallons
1 gallon = 3.8 litres or 3800 ml
52 gallons = 52 * 3800 = 197600 ml
Mass of gasoline = volume *density
Mass of gasoline = 197600 ml * 0.702 g/ml
Mass of gasoline = 138715.2 g
Equation of reaction:
2C8H18 + 25O2 ---> 16CO2 + 18H2O
2 moles of octane produces 16 moles of CO2
Molar mass of octane = 114 g/mol; molar mass of CO2 = 44 g/mol
114 * 2 g of octane = 44 * 16 g of CO2
138715. 2 g of octane produces = (138715.2 * 44 * 16) / 114 * 2 of CO2
Mass of CO2 produced = 428313.6 g of CO2 = 428.3136 Kg
Mass of CO2 produced in -lb weight = 428.3136 * 2.205
Mass of CO2 produced per year = 944.43 -lb CO2
Since 944.43-lb is close to 1000 -lb, therefore, it is a reasonable statement.
i too used it
i thought it will help
nice time. .....
Explanation:
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