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3 years ago

Does anybody know the answer to these two questions ?

Chemistry

1 answer:

Serjik [45]3 years ago

4 0

the first is hydroxide. I believe d is the second one but I'm not 100% positive so you may want to get a second opinion

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Which of the following elements would be predicted to be the best conductor of electricity? sodium (Na) germanium (Ge) sulfur (S

lubasha [3.4K]

Na because its a metal. Metals are the best conductors. S and Ne are nonmetals. and Ge is a metalloid. (Metalloids are semi conductors)

4 0

3 years ago

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Which action do researchers take to make advances in science?

melamori03 [73]

The action that researchers take to make advances in science would be conducting experiments to test their hypothesis. By doing such, they are able to know whether the hypothesis is true or not. Hope this answers the question. Have a nice day.

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3 years ago

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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.

8 0

3 years ago

Consider the element carbon. How many electrons can be found in a carbon atom? How many are valence electrons?

Eva8 [605]

Answer:

option B= 6 : 4

Explanation:

Properties:

1. Carbon have six electron and six proton.

2. The two electrons are present in first shell while remaining of four electrons are present in the second shell.

3. it is non-metallic element and present in the group fourteen of periodic table.

4. its atomic mass is 12.0107 u.

5. its melting and boiling point is 3550 °C and 4827 °C respectively.

Uses:

1. it is used as a fuel in the form of coal.

2. in the form of graphite it is used in dry cells, as a lubricant, in pencil and high temperature crucible.

3. it is also used in jewelry in the form of diamond and because of its hard nature used in industries for drilling, polishing, cutting and grinding.

4. carbon black powder is used in printer ink.

5. its most common alloy with iron is steel.

6. it form variety of compound with number of other elements like nitrogen, hydrogen, oxygen etc.

Electronic configuration:

1s2, 2s2, 2p2

Isotopes of carbon:

There are fifteen isotopes of carbon from C8 - C22. The isotopes C12 and C13 are stable while C14 is radioactive.

4 0

3 years ago

The equilibrium: 2 NO2(g) \Longleftrightarrow&iff; N2O4(g) has Kc = 4.7 at 100ºC. What is true about the rates of the forwar

Sergeeva-Olga [200]

Answer:

Initial: forward rate > reverse rate
Equilibrium: forward rate = reverse rate

Explanation:

2NO₂(g) → N₂O₄(g) Kc=4.7

The definition of equilibrium is when the forward rate and the reverse rate are equal.

Because in the initial state there's only NO₂, there's no possibility for the reverse reaction (from N₂O₄ to NO₂). Thus the forward rate will be larger than the reverse rate.

7 0

3 years ago