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2 years ago

Help please! I don’t know what subject to pick this is science tho!!!!!!!!!!!!!!!

Chemistry

1 answer:

miss Akunina [59]2 years ago

5 0

Answer:

Explanation:

Because it decreases from October trough december

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What type of reaction is shown below? a) Addition reaction b) Esterification

Gemiola [76]

Answer:

a) Addition reaction, is your answer

6 0

2 years ago

What is the concentration (m) of sodium ions in 4.57 l of a.847 m na3p solution?

drek231 [11]

A group of environmentalists were discussing the benefits and drawbacks associated with using fossil fuels. Which argument best fits the conversation?
Fossil fuels are cheaper than alternative forms of energy.Fossil fuel reserves will never be depleted.Fossil fuels are easily renewed. Fossil fuel use does not affect the environment.

8 0

2 years ago

When a 0.245-g sample of benzoic acid is combusted in a bomb calorimeter, the temperature rises 1.643 ∘C . When a 0.260-g sample

sveticcg [70]

Answer:

The heat of combustion per moles of caffeine is 4220 kJ/mol

Explanation:

Step 1: Data given

⇒ When benzoic acid sample of 0.245 grams is burned the temperature rise is 1.643 °C

⇒ When 0.260 gram of caffeine is burned, the temperature rise is 1.436 °C

⇒ Heat of combustion of benzoic acid = 26.38 kJ/g

Step 2: Calculate the heat released: for combustion of benzoic acid

0.245 g benzoic acid * 26.38 kJ/g = 6.4631 kJ

Step 3: Calculate the heat capacity of the calorimeter:

c = Q/ΔT

Q = 6.4631 kJ / 1.643°C = 3.934 kJ/ °C

Step 4: Calculate moles of a 0.260 g sample of caffeine:

Moles caffeine = Mass caffeine / Molar mass caffeine

0.260 grams/ 194.19 g/mol = 0.0013389 moles

Step 5: Calculate heat released: for combustion of caffeine

Q = c * ΔT

Q = 3.934 kJ/°C * 1.436 °C = 5.65 kJ

Step 6: Calculate the heat of combustion per mole of caffeine

5.65 kJ / 0.0013389 moles = 4219.9 kJ/mol ≈ 4220 kJ/mol

The heat of combustion per moles of caffeine is 4220 kJ/mol

4 0

3 years ago

The statement “the scientific process is open ended” means:

mina [271]

Answer:

think it helps you

<h2>Explanation:</h2>

The statement “the scientific process is open ended” means: Would an element with 7 valence electrons be more or less reactive than an element with 3 valence electrons? Element 1 is a hard dark-red solid

4 0

2 years ago

Why the measured pressure of a gas under conditions that are very close to those that would result in condensation will be lower

Snowcat [4.5K]

Answer:

Inter-molecular forces and molecular volumes are the chief reasons for lower measured pressure

Explanation:

The kinetic theory assumes that gas particles occupy a negligible fraction of the total volume of the gas. It also assumes that the force of attraction between gas molecules is zero.

However, during high pressure, the volume of the gas particles are not negligible compare to the total gas volume and as such the volume of a real gas under such condition is higher than the Ideal gas. Vander-waal attempted to modify the ideal gas equation by subtracting the excess volume from the ideal equation. The increased volume is the reason the measured pressure of a real gas is less than an ideal gas

On the other hand, close to condensation, the other assumption of negligible forces of attraction becomes invalid. As inter-molecular distances decrease, inter-molecular forces increase reducing the bombardment of the wall of the container due to restricted particle movement and lower measured gas pressure.

3 0

2 years ago