Which Statement Best Describes The Light That Will Cause Emission Of Electrons From A Given Metal Through (2023)

Chemistry High School

Answers

Answer 1

The correct answer: (b) light with any intensity above a certain frequency

The explanation:

when Energy of a photon : E = hf

- The photoelectric effect works like this:

- If you shine light of high enough energy on to a metal, electrons will be emitted from the metal. Light below a certain threshold frequency, no matter how intense, will not cause any electrons to be emitted. Light above the threshold frequency, even if it's not very intense, will always cause electrons to be emitted.

Answer 2

Answer:

Explanation:

Related Questions

All chemicals which contain OH in the formula are bases.
a. True
b. false

Answers

B. false I hope this help

Answer:

false

Explanation:

A is a heterogeneous mixture in which the particles settle to the bottom.

Answers

There are two types of mixture depending on the distribution of the components in the mixture.Homogeneous mixtures are mixtures which has uniform properties all throughout the solution while heterogeneous mixtures are the opposite they do not exhibit uniformity in any property. Example for a homogeneous is a salt solution where at any point you get a sample the properties are the same. For the heterogeneous mixture, a mixture of sand and salt where at any sampling point the properties are not the same.

suspension should be correct

a suspension

the particles are big enough to settle

a colloid

the particles are too small to ever settle

a solution

homogeneous mixture of two or more substances

Stained glass can be useful for _____________________ a. transmitting light and displaying colorful images.
b. churches to draw in new patrons who want to view its beauty from inside.
c. reflecting and absorbing light, as well as displaying colorful images.
d. creating mirrored images of light and colors on the surrounding walls of a religious structure.

Answers

Stained glass can be useful for churches to draw in new patrons who want to view its beauty from inside.

What is stained glass?

Stained glass is defined as a glass material which is made colored by means of adding metallic salts during the manufacturing process which imparts color to the glass.

These are used in many decorative purposes like decorating windows . The colors are imparted to the glass by mixing metal oxides into the colorless glass in its melted state.Sometimes fusion of a colored glass with a plain glass to make a stained glass is also used.

Stained glass is also prepared by glass paint where in streaks are introduced in glass by means of light firing in a furnace or a kiln.Silver stain is a range of compounds where in silver compound are mixed with binding substances and then applied to surface of glass,which are then fired in a furnace or in a kiln.

Learn more about stained glass,here:

brainly.com/question/29775274

#SPJ5

A. transmitting light and displaying colorful imaged.

Salt acts as an antifreeze.
a. True
b. false

Answers

Answer:

It's true

Explanation:

An example can be observed when the people add salt on the road surface to avoid icing. The salt water mixture is frozen at approximately a temperature of -21°C and not at a temperature of 0°C as it would be in the case of water. Salt when dissolved in water releases heat, thereby contributing to defrost ice. This is the same principle that is used for car antifreeze, which is to lower the freezing point.

A. I think that is the a answer. Not to sure

Einstein’s Theory of Relativity was built on the research and ideas of other scientists. The Theory of Relativity proposes that the speed of light is a constant. Which of the following statements explains why this is considered to be a scientific theory?

Answers

Einstein’s Theory of Relativity was built on the research and ideas of other scientists. The Theory of Relativity proposes that the speed of light is aconstant. Thestatement thatexplains why this is considered to be a scientific theory is that the majority of the scientific community voted on this theory over other possible explanations.

Answer:

The correct answer will be option-It is the best explanation because it supports the beliefs and opinions of most scientists.

Explanation:

Albert Einstein is known for his theory of relativity which states that energy is a converted form of mass to the square of the speed of light which is constant.

Albert Einstein was a theoretical physicist who used the facts and data from the papers of the previous physicist. Although he used the facts his theory became one of the important theory in the physics world as it explained the path of the light and the form in which it travels.

This theory is well accepted today as it was supported by the experiments and observation of the other works of different scientist. This led to the acceptance of the theory worldwide.

Thus, the selected option is the correct answer.

How much heat is released by the combustion of 2 mol of methane?
Use mc019-5.jpg.

Answers

From literature, the heat of combustion of methane is 55.5 MJ/kg methane. to account for the 2 mol of methane given we convert 2 mol to kg which is determined by multiplying 2 mol by molec.weight (16g/mol) divided by 1000 to convert to kg. This is equal to 0.032 kg methane. We multiply this to 55.5 MJ/kg.The total heat released is 1.776 MJ.

Given the balanced equation representing a reaction: 2NaCl -> 2Na + Cl2 A 1170. gram sample of NaCl completely reacts, producing 460. grams of Na. What is the total mass of Cl2 produced?

Answers

Given the stoichiometric equation above and the amount of NaCl needed to produce the products, we can determine the amount of products produced. A 1170 gram NaCl using stoichproduces 460 grams Na. This means the reaction makes a 100% conversion after. So, the amount of Cl2 produced from stoichis 709.61 grams.

Answer:

710.g

Explanation:

[05.03]What is the pressure, in mm Hg, of 2.50 moles of an ideal gas if it has a volume of 50.0 liters when the temperature is 27.0° C? 84.2 mm Hg 289 mm Hg 617 mm Hg 936 mm Hg

Answers

Assuming ideal gas law applies to the problem, we find the pressure from thegiven volume, temperature and number of moles. The ideal gas equation is PV=nRT. R is 0.0821 L atm/ mol K. Substituting the data given, P= (2.50 moles)(0.0821 L atm/ mol K)(27+273 K)/(50 L)= 1.2315 atm. This is equivalent to 936 mm Hg.

if measurements of a gas are 75l and 300 kilopascals and then the gas is measured a second Time and found to be 50L describe what had to happen to the pressure

Answers

In this problem, the ideal gas equation PV=nRT is applied. In this relationship, volume is inversely proportional to pressure. Hence, pressure increases when volume decreases, vice versa. In this case, volume is decreased from 75 to 50 L, so the pressure is expected to increase above 300 kilopascals.

In an exothermic reaction the bonding energy of the product is ?

Answers

In an exothermic reaction, heat is released. Heat released is determined by finding the difference of the total bonding energy of the product and the reactants. Since the heat released is negative, the bonding energy of the products should be greater than that of the reactants.

Which is a characteristic of a nonelectrolyte? A. It does not dissociate or ionize in water.
B. It partially dissociates or ionizes in water.
C. It conducts electricity poorly.
D. It conducts electricity extremely well.

Answers

Answer: Option (A) is the correct answer.

Explanation:

Non-electrolytes are the substances which do not dissociate into a solution or water to form ions.

Since, non-electrolytes do not dissociate into ions. Hence, they do conduct electricity.

Thus, we can conclude that it does not dissociate or ionize in water is a characteristic of a non-electrolyte.

Non-electrolytes are neither partially ionizable nor do they conduct electricity poorly. Therefore, out of the given options, only option (A) is the correct answer.

It is A on edge test

What is the result of multiplying (2.5 × 1010) × (3.5 × 10-7)? Use the correct number of significant digits.

Answers

Answer : The answer will be

Explanation :

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

Answers

The result of multiplying that equation is 70,700.

CuCl2 + 2NaNO3 mc023-1.jpg Cu(NO3)2 + 2NaCl What is the percent yield of NaCl if 31.0 g of CuCl2 reacts with excess NaNO3 to produce 21.2 g of NaCl?

Answers

The stoichiometric ratio of CuCl2 to NaCl is 1 is to 2. The stoichiometric ratio of 31.0 g CuCl2 is 26.95 grams of NaCl by converting the amount of CuCl2 to mole and multiplying by 0.5 and molar mass of NaCl.This amount is equal to 78.65% yield.

Which of the following reactions is endothermic? H2(g) + ½O2(g) → H2O(g), ΔH = -57.82 kcal
½N2(g) + O2(g) + 8.1 kcal → NO2(g)
½N2(g) + 3/2H2(g) → NH3(g) + 11.0 kcal
C(diamond) + O2(g) → CO2, ΔH = -94.50 kcal

Answers

Answer:

2) ½N2(g) + O2(g) + 8.1 kcal → NO2(g)

Explanation:

Chemical reactions in general can be classified as endothermic and exothermic reactions.

Endothermic reactions are accompanied by the absorption of energy. Here, the enthalpy (ΔH) change of the reaction is positive.

Exothermic reactions are accompanied by the release of energy. Here, the enthalpy (ΔH) change of the reaction is negative.

1)H2(g) + ½O2(g) → H2O(g), ΔH = -57.82 kcal

Here, ΔH is negative, hence exothermic

2)½N2(g) + O2(g) + 8.1 kcal → NO2(g)

Here, energy is being absorbed, hence endothermic

3) ½N2(g) + 3/2H2(g) → NH3(g) + 11.0 kcal

Here, energy is released, hence exothermic

4)C(diamond) + O2(g) → CO2, ΔH = -94.50 kcal

Here, ΔH is negative, hence exothermic

An exothermic reaction releases heat having a negative gross heat of reaction. The endothermic reaction, on the other hand, has a positive gross heat of reaction. Among the choices, the endothermic reaction is the third reaction having a positive heat of reaction.

Which statement best describes John Dalton’s use of creativity in his work? He reinterpreted and retested Joseph Proust’s results.
He used a scientific method to conduct his experiment.
He wrote his results down as four parts of the atomic theory.
He verified Democritus’s idea that matter was composed of atoms.

Answers

I think that the use of creativity in the sciences entails that one produce something out of nothing or from another thing. With this, I think that the thirdoption, "He wrote down his results as four parts of the atomic theory" is the manifestation of thecreativity of John Dalton.

its A) He reinterpreted and retested Joseph Proust’s results.

Drawing a conclusion derived from knowledge of an established principle is called deductive reasoning. True or false?

Answers

Answer: TRUE

Explanation:

Deductive reasoning is a process in which a conclusion is drawn on the basis of similarities and concordance with pre- proposed principles and multiple premises which are expected and assumed to be true.

In simple words the deductive reasoning is based upon conclusion which is derived from one or more statements or principles which are expected to be true.

On the basis of the above explanation, the statement Drawing a conclusion derived from knowledge of an established principle is called deductive reasoning. is true.

That would be correct.

An excellent tool to gauge the reliability of any theory is its capacity to generate correct? a.models b.predictions c.data d.hypotheses.

Answers

An excellent tool to gauge the reliability of any theory is its capacity to generate correct hypotheses. Hypotheses is validated by theories, and theories make up laws.

Answer:

hypotheses

Explanation:

How many grams of calcium phosphate can be produced when 89.3 grams of calcium chloride reacts with excess sodium phosphate? Unbalanced equation: CaCl2 + Na3PO4 → NaCl + Ca3(PO4)2

Show, or explain, all of your work along with the final answer.

Answers

The grams of calcium phosphate that can be produced when 89.3 grams of calcium chloride reacted with excess sodium phosphate is

83.08 grams of calcium phosphate

calculation

Step 1: write a balanced chemical equation

3CaCl₂ + 2Na₃Po₄ →6NaCl + Ca₃(PO₄)₂

step 2: find the moles of CaCl₂

moles = mass÷ molar mass

from periodic table the molar mass of CaCl₂ = 40 +( 2 x 35.5) =111 g/mol

moles = 89.3 g÷111 g/mol = 0.805 moles

Step 3: use the mole ratio to determine the moles of Ca₃(PO₄)₂

CaCl₂: Ca₃(PO₄)₂ is 3:1 therefore the moles of Ca₃(PO₄)₂ =0.805 x 1/3 =0.268 moles

Step 4: find mass of Ca₃(PO₄)₂

mass = moles x molar mass

from periodic table the molar mass of Ca₃(PO₄)₂ = (40 x3) +[ 31 +(16 x4)]2 =310 g/mol

mass is therefore =0.268 moles x 310 g/mol =83.08 grams

How many grams of sodium oxide can be produced when 55.3 g Na react with 64.3 g O2? Unbalanced equation: Na + O2 → Na2O

Show, or explain, all of your work along with the final answer.

Answers

Answer : The amount of sodium oxide produced is, 74.40 grams

Solution : Given,

Mass of sodium = 55.3 g

Mass of = 64.3 g

Molar mass of sodium = 23 g/mole

Molar mass of = 32 g/mole

Molar mass of = 61.9 g/mole

First we have to calculate the moles of sodium and oxygen.

Moles of Na =

Moles of =

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction will be,

From the balanced reaction we conclude that

4 moles of sodium react with 1 mole of oxygen

2.404 moles of sodium react with moles of oxygen

Excess moles of oxygen = 2.009 - 0.601 = 1.408 moles

That means sodium is a limiting reagent and oxygen is an excess reagent.

Now we have to calculate the moles of sodium oxide.

From the reaction we conclude that,

4 moles of sodium react to give 2 moles of sodium oxide

2.404 moles of sodium react to give moles of sodium oxide

Now we have to calculate the mass of sodium oxide.

Therefore, the amount of sodium oxide produced is, 74.40 grams

Given the two amounts of reactants, we get the limiting reactant between the two. We convert each to mole and divide them to their corresponding stoichiometric coefficient. we balance first above, that is 4Na+O2=2Na2O. hence, for Na that is 0.60 mole and oxygen is 2.00 mole. We follow the smaller amount, Na, hence the amount of sodium oxide in grams is 74.53 grams.