Determine the mass of 2.35 x 1024 molecules of Ca(NO3)

Calculate the frequency of electromagnetic wave with the wave length 344nm ( hint: use dimensional analysis)

Svetlanka [38]

Frequency = speed of light
---------------------------
wavelength

= 3 x 10^8
------------------------
344 x 10^-9

= 8.72 x 10^14 Hz.

Hope this helps!

5 0

3 years ago

28. Which statement is INCORRECT regarding radiation?

mash [69]

Answer:

Radiation is energy. It can come from unstable atoms that undergo radioactive decay, or it can be produced by machines. Radiation travels from its source in the form of energy waves or energized particles. There are different forms of radiation and they have different properties and effects.

Related information in Spanish (Información relacionada en español)

On this page:

Ionizing and non-ionizing radiation

Electromagnetic spectrum

Types of ionizing radiation

Periodic Table

Non-Ionizing and Ionizing Radiation

There are two kinds of radiation: non-ionizing radiation and ionizing radiation.

Non-ionizing radiation has enough energy to move atoms in a molecule around or cause them to vibrate, but not enough to remove electrons from atoms. Examples of this kind of radiation are radio waves, visible light and microwaves.

Ionizing radiation has so much energy it can knock electrons out of atoms, a process known as ionization. Ionizing radiation can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes. Ionizing radiation comes from x-ray machines, cosmic particles from outer space and radioactive elements. Radioactive elements emit ionizing radiation as their atoms undergo radioactive decay.

Radioactive decay is the emission of energy in the form of ionizing radiationHelpionizing radiationRadiation with so much energy it can knock electrons out of atoms. Ionizing radiation can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes.. The ionizing radiation that is emitted can include alpha particles, beta particles and/or gamma raysHelpgamma raysA form of ionizing radiation that is made up of weightless packets of energy called photons. Gamma rays can pass completely through the human body; as they pass through, they can cause damage to tissue and DNA.. Radioactive decay occurs in unstable atoms called radionuclides.

Explanation:

8 0

3 years ago

Please Help! Thank You

Ivanshal [37]

Explanation:

the answer is true because I had this question and got it right

3 0

2 years ago

Many elements bond to carbon by exchanging electrons. true or false.

Sliva [168]

If a metal is bonded to carbon, they form ionic bonds. If a nonmetal forms a bond with carbon, they form covalent bond. Ionic bond requires metals to give away electrons to form cations and nonmetal to gain/accept electron to form anions. Covalent bond requires sharing of electrons between both elements. So if you meant exchange as in covalent bond, then no. Not many nonmetal elements form bonds with carbon as there are more metal elements in the periodic table.

8 0

3 years ago

Read 2 more answers

THIS IS A THREE PART QUESTION IF YOU CAN HELP IT WOULD BE REALLY APPRECIATED SO I DONT FAIL.

Nostrana [21]

Answer:

1. B = 1.13M

2. A. 8.46%

3. D = 0.0199

Explanation:

1. Molarity of a a solution = number of moles of solute/ volume of solution in L

Number of moles of solute = mass of solute/molar mass of solute

Molar mass of NaC₂H₃O₂ = 82 g/mol, mass of NaC₂H₃O₂ = 245 g

Number of moles of NaC₂H₃O₂ = 245 g / 82 g/mol = 2.988 moles

Molarity of solution = 2.988 mols/ 2.65 L = 1.13 M

2. Percentage by mass of a substance = mass of substance /mass of solution × 100%

Mass of 2.65 L of water = density × volume

Density of water = 1 Kg/L = 1000 g/L; volume of waterb= 2.65 L

Mass of water = 1000 g/L × 2.65 L = 2650 g

Mass of solution = mass of water + mass of solute = 245 + 2650 =2895 g

Percentage by mass of NaC₂H₃O₂ = 245/2895 × 100% = 8.46%

3. Mole fraction of NaC₂H₃O₂ = moles of NaC₂H₃O₂/moles of solution

Moles of water = mass /molar mass

Mass of water = 2650 g; molar mass of water = 18 g/mol

Moles of water = 2650 g / 18 g/mol = 147.222 moles

Moles of solution = moles of solute + moles of water = 147.222 + 2.988 = 150.21

Moles of NaC₂H₃O₂ =2.988 moles

Moles fraction of NaC₂H₃O₂ =2.988/150.21 = 0.0199

6 0

3 years ago