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3 years ago

I have 2 Valence electrons and 1 energy levels

Chemistry

2 answers:

ladessa [460]3 years ago

8 0

Answer:

Hydrogen (H) and helium (He) have a valence shell containing one and two electrons respectively. They make up the first period (row) of the periodic table. Their valence electron/s are in the first energy level (n=1) , as is denoted by 1s1 and 1s2.

Explanation:

Logic... if its wrong imma cry

natima [27]3 years ago

3 0

Answer:

Hydrogen(H) and Heluim(He)

Explanation:

These are the only two valennce electrons and 1 energy levels.

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The specific branch of chemistry that focuses on molecules such as salts and water that constitute non-living matter, but are st

Soloha48 [4]

Answer: Inorganic chemistry

Explanation:

Inorganic chemistry can be defined as the branch of chemistry which studies the behavior of the inorganic compounds. Inorganic compounds are those compounds which lack carbon hydrogen bonding. The carbon monoxide, carbon dioxide, sodium chloride and water are the examples of inorganic compounds. This branch also studies the effect of these chemical compounds on the living things. The water and salts are chemicals which regulate the chemical and physiological reactions in the body.

5 0

3 years ago

A solution contains two isomers, n-propyl alcohol and isopropyl alcohol, at 25°C. The total vapor pressure is 38.6 torr. What ar

Leona [35]

Answer:

Mole fraction of alcohols in liquid phase $x_1=0.2727\& x_2=0.7273$ .

Mole fraction of alcohols in vapor phase $y_1=0.1468\& y_2=0.8516$ .

Explanation:

The total vapor pressure of the solution = p =38.6 Torr

Partial vapor pressure of the n-propyl alcohol = $p^{o}_1=21.0 Torr$

Partial vapor pressure of the isopropyl alcohol = $p^{o}_2=45.2 Torr$

$p=x_1\times p^{o}_1+x_2\times p^{o}_2$ (Raoult's Law)

$p=x_1\times p^{o}_1+(1-x_1)\times p^{o}_2$

$38.6 Torr=x_1\times 21.0 Torr+(1-x_1)\times 45.2 Torr$

$x_1=0.2727$

$x_2=1-0.2727=0.7273$

$x_1\& x_2$ is mole fraction in liquid phase.

Mole fraction of components in vapor phase $y_1\& y_2$

$p_1=y_1\times p$ (Dalton's law of partial pressure)

$y_1=\frac{p_1}{38.6 Torr}=\frac{p^{o}_1\times x_1}{38.6 Torr}$

$y_1=\frac{21.0 Torr\times 0.2727}{38.6 Torr}=0.1468$

$y_1=\frac{p_2}{38.6 Torr}=\frac{p^{o}_2\times x_2}{38.6 Torr}$

$y_2=\frac{45.2 Torr\times 0.7273}{38.6 Torr}=0.8516$

Mole fraction of alcohols in vapor phase $y_1=0.1468\& y_2=0.8516$

5 0

3 years ago

According to the cooling curve, what is the approximate freezing point of the substance?

Dmitry_Shevchenko [17]

Correct answer: B

Cooling curve is the plot of temperature versus time as the sample is allowed to cool. In a cooling curve, we start at a temperature greater than the boiling point. At this temperature, the sample is in gaseous state. At the boiling point, there is no change in temperature as the gaseous and liquid states are in equilibrium. As the temperature reduces further, the liquid starts to condense and at the melting point of the sample the liquid undergoes phase transition to solid state. At the melting temperature, a second plateau is observed as the temperature remains unchanged. At temperatures below the melting point, the sample exists as a solid.

So from the curve, the second plateau is observed at around -111 $^{0}C$ . This point represents the phase transition from liquid to solid state.