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2 years ago

Energy is conserved in chemical reactions. It is neither created nor_____

Chemistry

1 answer:

aivan3 [116]2 years ago

6 0

Answer:

destroyed, from, endothermic

Explanation:

Energy is conserved in chemical reactions. It is neither created nor destroyed but can be transferred from one form to another.

An exothermic reaction transfers energy from the reacting substance to the surroundings. The body of the container feels warm. An exothermic reaction has a negative value of enthalpy.

An endothermic reaction transfers energy from the surroundings to the reacting substance. The body of the container feels cold. In an endothermic reaction, enthalpy is positive.

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What numbers are shown in the symbol for a radioactive nuclide

Bingel [31]

The atomic # and the mass #.

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2 years ago

Read 2 more answers

What part of the atom determines if it will combine or break apart from other substances?

anzhelika [568]

<em>Answer:</em>

The atom consist of three parts, proton, neutron and electrons. The electrons determine that i will combine or beak from other substances.

<em>Explanation:</em>

The atom consist of three parts which are following

proton
neutron
electron

The proton and neutron form nucleus of an atom. It is present at center of an atom. They have positive charges, while electrons remained outside the nucleus in particular energy levels or shell around the nucleus.

During combination or breaking of substances ,only arrangements of electrons take place. The valence shell electrons decide whether they have to combine or not, while nucleus remained unchanged during any reactions.

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3 years ago

A weather balloon is filled with helium that occupies a volume of 5.57 104 L at 0.995 atm and 32.0°C. After it is released, it r

Alchen [17]

6.52 × 10⁴ L. (3 sig. fig.)

<h3>Explanation</h3>

Helium is a noble gas. The interaction between two helium molecules is rather weak, which makes the gas rather "ideal."

Consider the ideal gas law:

$P\cdot V = n\cdot R\cdot T$ ,

where

$P$ is the pressure of the gas,
$V$ is the volume of the gas,
$n$ is the number of gas particles in the gas,
$R$ is the ideal gas constant, and
$T$ is the absolute temperature of the gas in degrees Kelvins.

The question is asking for the final volume $V$ of the gas. Rearrange the ideal gas equation for volume:

$V = \dfrac{n \cdot R \cdot T}{P}$ .

Both the temperature of the gas, $T$ , and the pressure on the gas changed in this process. To find the new volume of the gas, change one variable at a time.

Start with the absolute temperature of the gas:

$T_0 = (32.0 + 273.15) \;\text{K} = 305.15\;\text{K}$ ,
$T_1 = (-14.5 + 273.15) \;\text{K} = 258.65\;\text{K}$ .

The volume of the gas is proportional to its temperature if both $n$ and $P$ stay constant.

$n$ won't change unless the balloon leaks, and
consider $P$ to be constant, for calculations that include $T$ .

$V_1 = V_0 \cdot \dfrac{T_1}{T_2} = 5.57\times 10^{4}\;\text{L}\times \dfrac{258.65\;\textbf{K}}{305.15\;\textbf{K}} = 4.72122\times 10^{4}\;\text{L}$ .

Now, keep the temperature at $T_1 =258.65\;\text{K}$ and change the pressure on the gas:

$P_1 = 0.995\;\text{atm}$ ,
$P_2 = 0.720\;\text{atm}$ .

The volume of the gas is proportional to the reciprocal of its absolute temperature $\dfrac{1}{T}$ if both $n$ and $T$ stays constant. In other words,

$V_2 = V_1 \cdot\dfrac{\dfrac{1}{P_2}}{\dfrac{1}{P_1}} = V_1\cdot\dfrac{P_1}{P_2} = 4.72122\times 10^{4}\;\text{L}\times\dfrac{0.995\;\text{atm}}{0.720\;\text{atm}}=6.52\times 10^{4}\;\text{L}$

(3 sig. fig. as in the question.).

See if you get the same result if you hold $T$ constant, change $P$ , and then move on to change $T$ .

6 0

2 years ago

All generators need some source of energy to rotate the coil or magnets.<br> True or False

Llana [10]

.energy mechanical needs it Answer:

Yes.

Explanation:

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2 years ago

If you want to find the force needed to pull a small car up a ramp, it would be best to use..

Katyanochek1 [597]

The answer is; A

By using a spring and determining the tension applied on the string by the car, it is possible to deduce the force. Determine the spring's initial tension as well as spring rate and working loads;

Rate = (Load – Initial Tension) ÷ Travel

k = (L – IT) ÷ T

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3 years ago