Hormones are chemicals secreted by the

How many moles are in 25.90 grams of NaCl

inessss [21]

Answer:

0.44316859040048207mol

Explanation:

7 0

2 years ago

Calculate the enthalpy for this reaction: 2C(s) + H2(g) ---> C2H2(g) ΔH° = ??? kJ Given the following thermochemical equation

nordsb [41]

Answer:

The enthalpy for given reaction is 232 kilo Joules.

Explanation:

$C_2H_2(g) + \frac{5}{2}O_2(g)\rightarrow 2CO_2(g) + H_2O(l), \Delta H^o_{1} = -1,123 kJ$ ...[1]

$C(s) + O_2(g)\rightarrow CO2(g), \Delta H^o_{2} = -340 kJ$ ..[2]

$H_2(g) + \frac{1}{2}O_2(g)\rightarrow H_2O(l) ,\Delta H^o_{3} = -211 kJ$ ..[3]

$2C(s) + H_2(g)\rightarrow C_2H_2(g),\Delta H^o_{4} =?$ ..[4]

2 × [2] + [3] - [1] ( Using Hess's law)

$\Delta H^o_{4}=2\times \Delta H^o_{2}+\Delta H^o_{3} - \Delta H^o_{1}$

$\Delta H^o_{4}=2\times (-340 kJ) + (-211 kJ) - (-1,123 kJ)$

$\Delta H^o_{4}=232 kJ$

The enthalpy for given reaction is 232 kilo Joules.

5 0

3 years ago

What would be another property that we Earthlings could use to classify stars?

Blizzard [7]

Answer: At the point when space experts take a gander at an article's range, they can decide its arrangement dependent on these frequencies. The most well-known technique stargazers use to decide the sythesis of stars, planets, and different articles is spectroscopy. This spread-out light is known as a range.

Explanation:

8 0

3 years ago

If 57.3 l of 0.497 m koh is required to completely neutralize 39.5 l of a CH3COOH solution. What is the molarity of the acetic a

bearhunter [10]

The molarity of the solution will be 0.72 m.

The majority of reactions take place in solutions, making it crucial to comprehend how the substance's concentration is expressed in a solution when it is present. The number of chemicals in a solution can be stated in a variety of ways, including.

The symbol for it is M, and it serves as one of the most often used concentration units. Its definition states how many moles of solute there are in a liter of solution.

Given data:

$V_{1} =57.3 L\\V_{2} = 39.5 L\\M_{1} = 0.497 m\\\\M_{2} = ?$

Molarity can be determined by the formula:

$M_{1} V_{1} = M_{2} V_{2}$

where, M is molarity and V is volume.

Put the value of given data in above equation.

57.3 × 0.497 m = M × 39.5 L

M = 0.72 m

Therefore, the molarity of the solution will be 0.72 m

To know more about molarity

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6 0

2 years ago

13

kifflom [539]

Answer:

Cultural Pest Control.

Explanation:

The cultural pest control is one of the oldest methos of pest control. This form of pest control is less practiced these days since curative form of pest control methods have been invented. The cultural pest control method is a preventive method of managing pest population. This pest control method takes long days of planning and execution.

<u>In this form of pest control method, the farmer had to change the timings of his farming operations in his field. This method requires careful timing in seeding and planting. This method of pest controlling requires knowledge and skills of fields</u>.

Thus the correct answer is the third option.

8 0

4 years ago