How does the number of valence electrons in atoms of metalloids explain why metalloids are semiconductors? They have one or two valence electrons, so they cannot lose electrons easily. They have one or two valence electrons, so they can lose or gain electrons. They have three to six valence electrons, so they cannot lose electrons easily. They have three to six valence electrons, so they can lose or gain electrons.

Answer:

Analytical science

Explanation:

Answer:

0

Explanation:

did research

Answer:

NO

Explanation:

It would be difficult to plot a line of best fit on the scattered graph of the activities of metal blocks as the activities would almost be the same horizontally on the graph and an attempt to draw/determine an intercept will be almost impossible.  The line of best fit is usually drawn to determine the relatedness/correlation of the variables.

Drawing intercept for the activities of the liquid is easier because a line of best fit can be easily placed between the clustered liquid activities on the scattered plot.

Answer:

Transcription is when you make a copy of the RNA from DNA. This is how the mRNA can leave the nucleus which exists to the cytoplasm and into ribosomes where protein synthesis occurs. Translation is what happens after transcription and this is where protein synthesis occusrs in the ribosomes/endoplasmic reticulum.

Explanation:

Answer:

(a) 3.33 mol Bi

(b) 140. g CO

Explanation:

Step 1: Convert 775g to moles

Bi Molar Mass - 208.98 g/mol × 2 = 417.98 g/mol

O Molar Mass - 16.00 g/mol × 3 = 48.00 g/mol

775g Bi₂O₃ ÷ 465.98 g/mol = 1.66316 mol Bi₂O₃

Step 2: Find the conversion from Bi₂O₃ to Bi

1 mole of Bi₂O₃ equals 2 moles of Bi

Step 3: Use Dimensional Analysis

1.66316 mol  ·  [tex]\frac{2 \hspace{2} mol \hspace{2} Bi}{1 \hspace{2} mol \hspace{2} Bi_2O_3}[/tex] = 3.32632 mol Bi

3.32632 mol Bi ≈ 3.33 mol Bi (3 significant figures)

Step 4: Find the conversion from Bi₂O₃ to CO

1 mole of Bi₂O₃ equals 3 moles of CO

Step 5: Use Dimensional Analysis

1.66316 mol  · [tex]\frac{3 \hspace{2} mol \hspace{2} CO}{1 \hspace{2} mol \hspace{2} Bi_2O_3}[/tex] = 4.98948 mol CO

Step 6: Find molar mass of CO and convert moles to grams

C - 12.01 g/mol

O - 16.00 g/mol

4.98948 mol CO · 28.01 g/mol = 139.775 g CO

139.775 g CO ≈ 140. g CO (3 significant figures)

Answer:

the answer is D

Explanation:

Answer:

False

Explanation:

Science is not based on primarily on peoples opinions and views of the subject matter whereas science is based on empirical observations and research for its validity.

Science aims to find answers to human questions related to the natural world through their research observation and experiments. Scientists and researchers provide valid proof of human questions so that people can trust them.

Science can change people's opinions regarding the natural world with valid proof and observational theories but science is not based on people's opinion.

Hence, the given statement is "false".

Answer: yall trust me on this one, i took one for the team. The answer is "C" or you can say 31 percent. boys get me 50 thanks.

Explanation:

The percentage of sunlight that hits the Earth's surface directly is 31 percent. The correct option is C.

Sunlight is the electromagnetic radiation transferred by the sun.

The sun is 93 million away from the earth, so it takes eight and half minutes to reach the sunlight to the earth.

Only 30 to 34 percent of light reaches the earth, and the remaining lights are reflected back by clouds and the earth itself.

Thus, the correct option is C, 31 percent.

Learn more about sunlight

https://brainly.com/question/27183506

Answer:

pH = 1.683

Explanation:

plz mark as brainliest if it helps

Answer:

measurement of the equilibrium concentration of an acidic product via titration with a strong base

Explanation:

The rate at which a reaction proceeds refers to how quickly the reaction is occuring. In other words, it is how quickly the reactants are changing to the products. According to the question, the rate of a reaction can be measured experimentally using the reactants' or products' properties e.g volume, pressure etc.

Since reactions must involve reactants and products, the manner in which either the reactants or products changes over time can be measured. For example; measurement of the absorbance of a colored reactant or product with time, measurement of the change in the partial pressure of a gas-phase reactant or product over time can be used.

However, a measurement of the equilibrium concentration of an acidic product via titration with a strong base will not tell us how fast the reaction is going because it is in an EQUILIBRIUM state i.e. reaction is occuring at an equal rate

Answer:

109°

Explanation:

According to Valence Shell Electron Pair Repulsion Theory, electron pairs on the valence shell of the central atom of a molecule must be positioned as far apart in space as possible to minimize repulsion between valence shell electron pairs.

The shape of a molecule depends on the number and type of electron pairs on the valence shell of its central atom. Lone pairs generally cause more repulsion than bond pairs of electrons.

The ideal bond angle for a molecule with four bonds is 109° which corresponds to a tetrahedral geometry. This enables the four bonds to spread as far apart in space as possible.

Answer:

attached below is the required solution

Explanation:

A) Zinc acetate + Sodium carbonate

B) barium nitrate + sodium sulfate

C ) lead ( II ) nitrate + sodium sulfate

D) Zinc acetate + sodium sulfate

E) barium nitrate + potassium iodide

F) Lead ( I ) nitrate + potassium iodide

G) Zinc acetate + potassium iodide

A net ionic equation shows the ions that underwent change in a reaction hence it excludes the spectator ions.

A metathesis reaction is one which the cations exchange anion partners in the products. A general example of a methathesis reaction is AX + BY ---> AY + BX.

The molecular and net ionic equation for the reactions are;

1) Zn(CH3COO)2(aq) + Na2CO3(aq) -----> ZnCO3(s) + 2CH3COONa(aq)

Net ionic equation; Zn^2+(aq) + CO3^2-(aq) ------>  ZnCO3(s)

2) Ba(NO3)2(aq) + Na2SO4(aq) ------> BaSO4(s) + 2NaNO3(aq)

Net ionic equation; Ba^2+(aq) + SO4^2-(aq) ------> BaSO4(s)

3) Pb(NO3)2(aq) +  Na2SO4(aq) ------> PbSO4(s) + 2NaNO3(aq)

Net ionic equation; Pb^2+(aq) + SO4^2-(aq) ------> PbSO4(s)

4) Zn(CH3COO)2(aq) + Na2SO4(aq) ------> ZnSO4(s) + 2CH3COONa(aq)

Net ionic equation: Zn^2+(aq) + SO4^2-(aq) ------>  ZnSO4(s)

5) Ba(NO3)2(aq) + 2KI(aq)  ------> 2KNO3(aq) + BaI2(aq)

There is no net ionic equation for this reaction.

6) Pb(NO3)2(aq) + 2KI(aq)  -------> PbI2(s) + 2NaNO3(aq)

Net ionic equation: Pb^2+(aq) + 2I^-(aq) ----->  PbI2(s)

7) Zn(CH3COO)2(aq) + 2KI(aq) -----> ZnI2(aq) + 2CH3COOK(aq)

There is no net ionic equation for this reaction

Learn more: https://brainly.com/question/1340582

Answer:

C=O

Explanation:

The nuclear magnetic resonance (NMR) spectroscopy is a method that employs the technique to observe the local magnetic fields are atoms. This analytical technique exploits sufficient differences in the frequency of nuclear magnetic resonance in protons and atoms within organic compounds that depend on their neighboring atoms.

Amongst all the given options, the carbonyl is the right option because the carbon is doubly bonded to the oxygen and the hybridization of this double bond is sp² hybridized, as a result, the electron density at the carbon possess a lower amount in order to have more magnetic field.

The increasing order of these chemical shifts are as follows:

C - X     <     [tex]\mathbf{C -O }[/tex]≅[tex]\mathbf{ \mathrm{-C\equiv C-}}}[/tex]   < -C≡N    < C=O

Answer:B

Explanation:

Answer:

20 m/s^2

Explanation:

given,

final velocity (v) = 6000m/s

initial velocity (u) = 0m/s

time taken (t) = 5 minutes

= 5×60second

= 300second

acceleration(a) = ?

we know that,

a = (v-u)/t

= (6000-0)/300

= 20 m/s^2

Answer:

c

Explanation:

Answer:

dez nuts. the forth quauter in ur girls buttr

Gas is well separated with no regular arrangement, liquids are close together and solids are tightly packed. Solid, liquid, and Gas are the state of substances at room temperature.

There are three state of substances:

The chair you are sitting on is a solid, the water you drink is liquid, and the air you breathe is a gas. The atoms and molecules don't change, but the way they move about does. Water, for example, is always made up of two hydrogen atoms and one oxygen atom.

Physical properties of a particular substance determine its state at room temperature. If both its normal melting point and its normal boiling point are below room temperature (20°C), the substance is a gas under normal conditions.

Oxygen is a gas at room temperature. If the normal melting point of a substance is below room temperature, the substance is a liquid at room temperature.

If both the normal melting point and the normal boiling point are above room temperature, the substance is a solid.

Therefore, solid, liquid and gas all exist as substances at room temperature.

To know more about state of substance, refer to below link:

https://brainly.com/question/7905041

#SPJ2

Answer:

A. Making decisions that help humans survive

B. Developing technologies that help humans thrive

C. Developing explanations based on facts

E. Gathering facts that explain natural events

Explanation:

The above are examples of the practices of how humans use science.

Science has been of tremendous help to humans in making decisions that make humans survive and develop technologies that help humans thrive. It has helped to gather and develop explanations that are based on facts. It has helped to explain natural events.

Answer:

A. Using materials and design techniques that reduce the negative

environmental impact of a structure

Explanation:

A P E X

Using materials and design techniques that reduce the negative

environmental impact of a structure. Hence, option A is correct.

Green design is the 'creation of buildings which are energy-efficient healthy, comfortable, flexible in use and designed for long life.

The word ‘Green’ represents designs which are eco-friendly and less harmful to humans and other organisms. It helps in the protection of natural resources such as water, air etc.

Green designs are also referred to as techniques and materials that reduce the negative environmental impact of a structure.

Hence, option A is correct.

Learn more about green design here:

https://brainly.com/question/27560699

#SPJ2

Answer:

The shape of an atom is not important so it is easier to treat atoms as spheres.

Explanation:

In considering the shape of an atom, we do not consider the shape of the orbitals individually.

Hence, we do not seek to determine the exact shape of the atom, rather we simply treat the atom as spheres. Even though most orbitals are not spherically shaped.

Given :

Mass of object , M = 14 g .

Volume of object , V = 3.5 mL .

To Find :

The density of the object .

Solution :

Density of an object is given by :

[tex]Density=\dfrac{Mass}{Volume}\\\\\rho=\dfrac{M}{V}\\\\\rho=\dfrac{14}{3.5}\ g/mL\\\\\rho=4\ g/mL[/tex]

Therefore , the density is 4 g/mL .

Hence , this is the required solution .

Answer:

Convection

Explanation:

Convection is the transfer of thermal energy by particles moving through a fluid.

Answer:

convection

Explanation:

trust

Answer:

Electrons, they circle the nucleus.

Answer:

2.0 mmole

Explanation:

The computation fo the amount of mmol is shown below:

As we know that

[tex]Mole = \frac{Given\ mass}{molar\ mass}[/tex]

where,

Given mass is 0.2 gm

The Molar mass is 96.2g/mol

Now

put these values to the above formula

So,

[tex]= \frac{0.2}{y96.2} \\\\= \frac{1}{481} mole[/tex]

Mile mole is

[tex]= \frac{1}{481}\times 1,000[/tex]

= 2.079

= 2.0 mmole

As

mole = 1,000^-1 mili mole

We simply applied the above formula so that the amount of mmole could come

The atom of alkaline earth metal has one more proton and one more electron than the alkali metal that is next to it to the left on the periodic table. Then the atomic number of the alkali metal is one unit less than the atomic number of the alkaline earth metal next to it

Answer:

A) The alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion.

Explanation:

Let's evaluate each answer.

A: The alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion.

This means that the alkali metal atom has to lose 1 valence electron to form a +1 ion while the alkaline earth metal atom has to lose 2 valence electrons to form a +2 ion. This is accurate because alkali metal atoms have 1 valence electron while alkaline earth metal atoms have 2, so the statement is correct.

B: The alkali metal atom forms a +2 ion, while the alkaline earth metal atom forms a +1 ion.

This would mean that the alkali metal atom has to lose 2 valence electrons to form a +2 ion, while the alkaline earth metal has to lose 1 valence electron to form a +1 ion. This is incorrect because alkali metal atoms only have 1 valence electron and will become a +1 ion when losing that electron, while alkaline earth metals have 2 valence electrons and will form a +2 ion upon losing them.

C: The alkali metal atom has one less shell of electrons than the atom of the alkaline earth metal.

This would mean that the alkali metal atom would be located one period higher up than the alkaline earth metal atom. This is untrue, because the question states that the alkali metal atom is located directly next to the alkaline earth metal atom, so they have the same amount of electron shells.

D: The alkali metal atom has one more shell of electrons than the atom of the alkaline earth metal.

This would mean that the alkali metal atom would be located one period lower on the periodic table than the alkaline earth metal atom. Similar to the previous statement, this is untrue because the question states that they are located directly next to each other, or on the same period.

(Also, I just took this quiz and e2020 says it's right.)