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2 years ago

PLS PLS PLS PLS HELP IM STRUGGLING

Chemistry

1 answer:

andriy [413]2 years ago

5 0

Answer:

A. 4 only

Explanation:

One of the tests for purity is by determining the melting point of a substance. A pure substance has a sharp meting point.

If the solid in question is a pure solid, when it is heated, it will exhibit a sharp melting point. Mixtures however melt over a range of temperatures due to the presence of impurities in the solid.

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Atoms like sodium and lithium often lose electrons, which makes them

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More reactive than others

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2 years ago

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Nitrogen and hydrogen react to produce ammonia.

Doss [256]

Answer:

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2 years ago

Two hydrogen atoms collide in a head on collision and end up with zero kinetic energy. Each then emits a photon of 121.6 nm (n=2

Zinaida [17]

Explanation:

Expression for the kinetic energy is as follows.

K.E = $\frac{1}{2}mv^{2}$

Now, total kinetic energy will be as follows.

K.E = $2 \times \frac{1}{2}mv^{2}$ = $m \times v^{2}$

Since, this energy converts into electromagnetic radiation of wavelength 121.6 nm.

Relation between energy and photon is as follows.

Energy of photon = $\frac{hc}{\lambda}$

= $\frac{6.626 \times 10^{-34} \times 3 \times 10^{8}}{121.6 \times 10^{-9}}$

= $1.63 \times 10^{-18} J$

$m \times v^{2} = 1.63 \times 10^{-18}$

v = $\sqrt{\frac{1.63 \times 10^{-18}}{1.67 \times 10^{-27}}$

= $3.12 \times 10^{4}$ m/s

Thus, we can conclude that atoms were moving at a speed of $3.12 \times 10^{4}$ m/s before the collision.

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3 years ago

Which statement about states of matter is correct? (1 point)

belka [17]

Answer:

Explanation:

If you add enough heat to a solid it eventually becomes a liquid

4 0

2 years ago

4. A student is doing experiments with CO2(q) . Originally a sample of the gas is in a rigid container at 299 Kand 0.70 atm. The

marta [7]

Answer:

b. 0,99atm

c. Answer is in the explanation

d. Answer is in the explanation

Explanation:

b. Using Gay-Lussac's law:

P₁T₂ = P₂T₁

P₁: 0,70 atm; T₂: 425K; P₂: ??; T₁: 299K

0,70atm×425K / 299K = <em>0,99 atm</em>

c. Using kinetic molecular theory, the increasing of temperature increases the kinetic energy of gas particles and if kinetic energy increases, the pressure increases. That means the increasing of temperature increases the pressure in the system.

d. Now, the increases in kinetic energy of gases increase the collisions betwen particles. As these intermolecular forces that are not taken into account in ideal gas law, the observed pressure will be different to the pressure predicted by ideal gas law.

I hope it helps!

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2 years ago