the half-life of cesium-137 is 30 years. suppose we have a 70-mg sample. (a) find the mass that remains after t years.

Answer: In this case, there are a total of 4 atoms (1 boron atom and 3 hydrogen atoms) bonded together in the molecule.

Explanation:  Borane is a chemical compound that contains one boron atom bonded to three hydrogen atoms. The chemical formula for borane is BH3, indicating that it contains one boron atom bonded to three hydrogen atoms. Borane is a molecule, which means it is composed of two or more atoms bonded together chemically. In this case, there are a total of 4 atoms (1 boron atom and 3 hydrogen atoms) bonded together in the molecule.

The Element is a pure substance that can only be separated into two or more simpler substance using chemical changes. elements can not broken down by a chemical reaction.

Elements are pure substances that cannot be transformed into more basic ones by physical or chemical processes. The most basic type of matter, an element has its own set of characteristics. Well-known elements are oxygen, iron, and gold, as examples. Simpler substances cannot be created from elements. Furthermore, no element can be chemically changed into another element. Pure substances are formed by only one kind of particle that may have a fixed or constant structure. An element is a pure material with only one type of atom that cannot be divided into two or more simpler substances through physical or chemical means.

to know more about pure substance please visit.

https://brainly.com/question/24830916

#SPJ4

liquid water at 50 °c is heated to steam at 150 °c. i)Water remains in the liquid phase between 50°C and 100°C. And it gains heat, which we calculate using the specific heat of H20 (l).ii) At 100°C, liquid water absorbs heat and condenses to form vapour. And we needed H for this (vapourisation).

iii) Water remains in the vapour phase between 100°C and 150°C. We also needed the specific heat of H2O(g) to calculate heat gain. As a result, it is clear that H(fusion) is irrelevant in this case. Specific heat is defined as the amount of heat required to raise the temperature of a unit mass of substance by one degree Celsius. Enthalpy of phase transformation is characterised as the heat change at constant temperature and pressure for per mole substances during phase transition.

Learn more about specific heat here:

https://brainly.com/question/11297584

#SPJ4

According to the claim, the substance in question is barium chloride, also known as BaCl₂.

For the purpose of overcoming these unfavorable design patterns, the SOLID tenets were created. Reducing dependencies allows engineers to alter one component of software without affecting others, which is the main objective of the SOLID principles. They are also meant to make designs simpler to comprehend, update, and expand.

A solid is distinguished by its rigidity and tolerance to external forces. A solid substance, unlike a liquid, doesn't quite flow to conform to the form of its containers or, like a gas, expand to cover the entire space.

To know more about Solid visit:

https://brainly.com/question/225975

#SPJ4

The complete question is-

You are presented with a white solid and told that due to carless labeling it is not clear if the substance is barium chloride, lead chloride or zinc chloride. When you transfer the solid to a beaker and add water the solid dissolves to give a clear solution. Next a Na2SO4 (aq) solution is added and a white precipitate forms. What is the identity of the unknown white solid?

a). BaCl₂

b). CaCO₃

c). MgCl₂

Place the atomic number subscript and mass number superscript to the left of the atomic symbol.

The chemical properties of an atom are determined by its atomic number and are represented by the symbol Z. The total number of nucleons in an atom is the atomic mass number. This value is represented by the symbol A.

Isotopes are members of a family of elements that have the same number of protons and a different number of neutrons. The number of protons in the nucleus determines the atomic number of an element on the periodic table. Isotopes are atoms of the same element that contain the same number of protons but different numbers of neutrons.

Learn more about Isotopes here:- https://brainly.com/question/14220416

#SPJ4

Answer:

0.072 J/kg*K

Specific Heat [[tex]\frac{Joules}{kilogram*Kelvin}[/tex]] = c = [tex]\frac{Q}{m(T_{2}-T_{1})}[/tex]

where Q [J] = Heat, m [kg] = mass, and ΔT [K] = change in temperature

Q = 200 J

m = 10 g

ΔT = 5 °C = 5 °C + 273 = 278 K

Specific Heat = c = (200 J) / (10 g * 278 K) = 0.072 J/kg*K

The solvent is said to be saturated when it has dissolved all the solute it can at a particular temperature.

The relationship between solvents and solutes is an important one in the study of chemistry. In order to understand the dynamics of this relationship, it is important to understand the concept of saturation. When a solvent has dissolved all the solute it can at a particular temperature, it is said to be saturated. In this essay, the significance of saturation in solvent-solute interactions will be discussed in detail.

At the most basic level, saturation is important because it helps to inform chemists of the maximum amount of solute that can be dissolved in a solvent at any given temperature. This information can be used to control the concentration of a solution and to ensure that it is within the desired range for a particular application.

Learn more about temperature:

https://brainly.com/question/20595779

#SPJ4

As shown in the figure below  [tex]H_2O_2[/tex] and [tex]NO_2^-[/tex] have have non linear structure and rest all given molecules have  linear structure.

[tex]H_2O_2[/tex] (Hydrogen peroxide) have open book like structure as shown in the figure below.

The geometry surrounding a central atom that is joined to two additional atoms at a bond angle of 180° is known as the linear molecular geometry in chemistry. When describing linear organic compounds with carbon centers, such as acetylene, sp orbital hybridization is frequently used.

To know more about Central atom click on below link:

https://brainly.com/question/29422259#

#SPJ4

The [OH-] of the 0.025 M weak acid solution will be equal to the pKA of the acid, 4.615.
What is weak acid solution?
A weak acid solution is a solution that contains an acid that is not completely ionized in water. Weak acids, such as acetic acid, have pH values between 4.5 and 6.0. These acids are not strong enough to completely break apart in water, leaving some of the molecules still intact. Because of this, weak acids form molecules that can react with other molecules, such as bases, in solution.
This is because the equilibrium of the acid dissociation reaction is reached with the same concentration of acid and its conjugate base in solution. The [H3O] will be equal to 0.025 M, as the acid is in dissociation equilibrium with its conjugate base. The pH of the solution can be calculated by taking the negative log of the [H3O], which will be 1.59. The pOH can be calculated by taking the negative log of the [OH-], which will be 4.615.
To know weak acid solution click-
https://brainly.com/question/9396848
#SPJ4

carbon tetrachloride has the highest boiling point.

Carbon tetrachloride is also known by many other names (such as tetrachloromethane) by IUPAC name.

The boiling point elevation of a liquid or a compound is defined as the boiling point of a liquid that is that will be higher when some other compound is added. It means that the solution has a higher boiling point than the solvent.

When a nonvolatile solute is added to a pure solvent like water, it results in the highest boiling point elevation.

Carbon tetrachloride, Kb = 5.03°C/m shows the highest boiling point elevation when it is used to make a 0.10 m non - electrolyte solution.

To know more about boiling point:

https://brainly.com/question/28203474

#SPJ4

The most common type of regenerated fiber, which is derived from cellulose and is mostly plant in origin, is rayon is True.

A natural source of regenerated cellulose, such as wood and other associated agricultural products, is used to create rayon, a semi-synthetic material. Its molecules resemble those of cellulose. Viscose is another name for it. Viscose fibres and films come in a wide variety of types and grades. Some mimic the appearance and feel of organic materials including silk, wool, cotton, and linen. Artificial silk is a common name for the materials that resemble silk.

To know more about Rayon refer here

https://brainly.com/question/13923474#

#SPJ4

Complete Question

The most common type of regenerated fiber, which is derived from cellulose and is mostly plant in origin, is rayon.

True

False

Answer: This is because the atomic radius increases with increasing electronic energy. This reduces the attraction for the valence electrons of other atoms, reducing reactivity.

Answer:

Calcium has a smaller radius in comparison to Potassium.

Explanation:

When we move down a group, the atomic radius increases, and when we move from left to right in a period, the atomic radius decreases. Since both Potassium and Calcium are in the 4th period, we have to look left to right. Calcium is to the right of Potassium making the radius smaller.

At 100 C, the temperature at which two phases are in equilibrium, liquid water begins to boil and change into the vapour phase. As a result, at 100 °C, the two phases are in balance.

The study of equilibrium relationships within or between phases, which corresponds to homogeneous and heterogeneous phase equilibria, is known as phase equilibria, which applies the principles of thermodynamics to the subject.

The term "phase equilibria" refers to the coexistence of two or more phases (in equilibrium). Chemical potential can be used to forecast the stability of phases since the most stable form of a substance will have the lowest chemical potential at the specified temperature and pressure.

The standard unit of measurement known as one atmosphere (atm) corresponds to the average atmospheric pressure at sea level and 15 degrees Celsius (59 degrees Fahrenheit). 1,013 millibars, or 760 millimetres (29.92 inches) of mercury, make up one atmosphere. As height rises, atmospheric pressure decreases.

To learn more about equilibrium Please click on the given link:

https://brainly.com/question/5081082

#SPJ4

The ratio of metal between cationic [+] atom and nonmetal anionic [-] atom in Na is 1:2 ,The correct option is D

Lewis electron is a very simplified representation of the valence shell electrons in a molecule. It is used to show how the electrons are arranged around individual atoms in a molecule. Electrons are shown as dots or for bonding electrons as a line between the two atoms.

Therefore Lewis dot symbols allow us to predict the number of bonds atoms will form and therefore the stoichiometry of a compound. The Lewis structure of a compound also indicates the presence or absence of lone pairs of electrons.

Learn more about lewis electron here: brainly.com/question/30010470

#SPJ1

A compound is a substance that can only be split into two or more compounds chemically.  

Compounds are compounds made up of two or more chemically coupled components that can only be broken down chemically into simpler substances. Compounds are compounds made up of two or more chemically coupled components that can only be broken down chemically into simpler substances. For instance, pure water is a compound since it contains solely H2O molecules. A compound is a substance that, due to the presence of multiple elements, can be divided into chemically simpler components. For instance, water is a substance made up of the elements oxygen and hydrogen. a material consisting of two or more components mixed chemically in a predetermined ratio.

to know more about substance please visit.

https://brainly.com/question/24372098

#SPJ4

3.97 mmol/L is the 15th percentile of chloride concentration values of blood chloride.

The 15th percentile of a normal distribution corresponds to the value of chloride below which 15% of the data lies. To determine this value for a normal distribution with a mean of 5 and a standard deviation of 1, we can use the standard normal distribution table or a calculator that can compute percentiles for a normal distribution.

Using a standard normal distribution table, we can find that the 15th percentile of a normal distribution with a mean of 0 and a standard deviation of 1 is -1.03. Since the mean of our distribution is 5 and the standard deviation is 1, we need to shift the value by 5 units to the right to find the 15th percentile of our distribution. Therefore, the 15th percentile value of chloride concentration is -1.03 + 5 = 3.97 mmol/L.

Alternatively, we can use a calculator that can compute percentiles for a normal distribution. For example, using the "NormDist" function in Microsoft Excel, we can calculate the 15th percentile value as follows:

=NORMDIST(3.97,5,1,TRUE)

This will return a value of 0.15, which indicates that the value of 3.97 mmol/L is the 15th percentile of the normal distribution.

It's important to note that this calculation assumes that the data follows a normal distribution. If the data is not normally distributed, the 15th percentile value may be different.

To know more about chloride please refer: https://brainly.com/question/1307733

#SPJ4

Question - Suppose that blood chloride concentration (mmol/L) has a normal distribution with mean 05 and standard deviation. Determine the 15 percentile value of chloride concentration.

If the sample is compressed to a volume of 11.4L, the pressure is  1.147 atm.

"Pressure" is defined as the thrust (force) applied to a surface per area. The ratio of force to area is another way to describe it (over which the force is acting).

Formula and Pressure's Unit:

Thrust/Area = Pressure (P)

Pascals (Pa) is the SI unit. 1 Pa = 1N/m2

For instance, it is simpler to hammer a sharp pin than dull pin. This is due to the fact that sharp pin's end has a lower surface area than blunt pin. This causes the pressure to rise.

Types of Pressure:

Calculation:

We can find [tex]P_{2}[/tex] by using the formula for Boyle's law:

[tex]P_{1} V_{1} = P_{2} V_{2}[/tex]

Since we are finding another pressure:

[tex]P_{2} = \frac{P_{1}V_{1}}{V_{2}}[/tex]

From the question we get:

[tex]P_{2} = \frac{(1.03)(12.7 ) }{11.4 }[/tex]

[tex]P_{2} = 1.147[/tex]

Therefore the pressure is 1.147 atm.

To learn ore about pressure visit:

https://brainly.com/question/18915714

#SPJ4

The phase transition that takes place when the pressure on a pure subsatnce is increased at a constant temperature is liquid to solid.

Raising the pressure increases the melting factor of maximum solids. That's why the melting factor line slopes ahead for maximum substances. Moving from stable to liquid with the aid of using converting the stress: You also can mess around with this with the aid of using searching at what takes place in case you lower the stress on a stable at consistent temperature. At standard conditions as temperature increases, maximum materials extrude from solid to liquid to gas, and at trendy temperature as strain increases, maximum materials change from gas to liquid to solid.

To learn more about phase transition check the link below:

https://brainly.com/question/29795678

#SPJ4

A polar covalent molecule link is a type of covalent bond in which the atoms are attracted to electrons in uneven amounts, resulting in unequal sharing. the term "polar bond" can also refer to a polar covalent bond.

Acetaminophen contains 3 polar bonds, these are created from the two carbon and oxygen bonds and one carbon and nitrogen bond with in the molecule due to the higher electronegativity within the oxygen and nitrogen compared to the carbon. Caffeine contains 6 polar bond ,these are created from the 2 carbon and oxygen bonds and 4 carbon and nitrogen bonds within the compound due to the higher electronegativity within the oxygen and nitrogen compared to the carbon. Phenacetin contains 2 polar bonds, these are molecule from the one carbon and oxygen bonds and another one carbon and nitrogen within the compound due to the higher electronegativity within the oxygen and nitrogen compared to the carbon. Aspirin contains 2 polar bonds, these polar bonds are molecule from the two carbon and oxygen bonds within the compound due to the higher electronegativity within the oxygen compared to the carbon.

learn more about polar bonds here:

https://brainly.com/question/3069993

#SPJ4

Leslie and Renee collaborating and choosing the design is because the design element applied here are the variety of shapes and variety of textures.

The building blocks that a visual artist or graphic designer utilises to create a successful composition are known as design elements.

A shape is a two-dimensional region that has an outline around it. Shapes can be categorised into three categories: geometric shapes, which are angular and mathematically consistent, and organic shapes, which are found in nature. Abstract forms that loosely resemble natural objects but aren't quite accurate

Texture is one of the design elements, it conveys the appearance or sensation of an object. Whether it is bumpy, velvety, or ribbed, tactile texture is a feeling of touch. Contrarily, visual texture refers to the imagined texture of the illustration, which can add visual interest and enhance the sensory experience.

Note that the full question is:

your local movie theater is having a contest to design their new promotion poster Leslie and Renee are collaborating and they chose to sign background because it applies which design element? select two options1. symmetry

2. variety of textures

3. variety of shapes

4. Unity of colors

To learn more about designing elements: https://brainly.com/question/13818137

#SPJ4

CO ligands is most likely to form a low-spin octahedral complex with iron(iii).  The energy difference between high and low spin is determined by the ligand mix and coordination stereochemistry.

For these model compounds, high spin optimised geometries yield structures with octahedral symmetry. D5 low spin will form an octahedral complex. Three of the five d orbitals will be filled with electrons, while the other two will be energy. These two empty low-spin can be sp3d2 hybridised (or d2sp3 hybridised) to form an octahedral complex. Because CN and NH3 are strong field ligands (from the spectrochemical series), the complexes [Fe(CN)6]4 and [Co(NH3)6]3+ are low spin.

To learn more about energy, click here.

https://brainly.com/question/1932868

#SPJ4

Fatty acid synthesis begins w/ carboxylation of acetyl CoA, occurs in cytoplasm, intermediates linked to acyl carrier protein, uses NADPH, a series of condensation, reduction, and dehydration reactions, committed step is formation of malonyl CoA, enzymes are joined in a multienzyme complex (Option A), while during fatty acid oxidation acetyl CoA is a product, takes place in the mitochondria, intermediates linked to coenzyme A, uses FAD and NAD⁺ (Option B).

Fatty acid synthesis refers to the metabolic pathways to generate a  fatty acid from acetyl-CoA and also the NADPH molecule,  while Fatty acid oxidation is the cellular respiration process to generate energy using fatty acids.

Therefore, with this data, we can see that fatty acid synthesis and oxidation are distinct in the sense that the last is involved in the generation of energy.

Learn more about Fatty acid synthesis here:

https://brainly.com/question/16252700

#SPJ1

97.17 years will be required until the 90sr is reduced to 1.0 ppm

Calculation :

Radiactive decays are always follow first order kinetics .

[tex]t_{1/2}[/tex] = 28.8 yr

for first order reaction,

kt = ln([A]0/[A]t)

where k = rate constant

           t = time

       [A]0 =initial concentration

       [A]t  = concentration at time t

And half cycle [tex]t_{1/2}[/tex] = 0.693/k

28.8 yr = 0.693/k

k = 0.024yr⁻¹

 [A]0 = 10.3 ppm

  [A]t  =  1.0 ppm

 k*t = ln([A]0/[A]t)

t * 0.024 = ln(10.3/1.0)

t= 2.332/0.024

t = 97.17 yr

Half-life in radioactivity, the time interval required for half of the nuclei in a radioactive sample to decay (spontaneously transform into other types of nuclei by releasing particles and energy), or equivalently, the time required for decay times Every second of interval radioactivity ...

Learn more about half-life here : https://brainly.com/question/1160651

#SPJ4

The volume of 15.8 M concentrated nitric acid required to completely react with 1.00 g of copper would be 0.004 L or 4 mL.

Concentrated nitric acid and copper react to produce hydrogen gas, nitrogen dioxide gas, and copper (II) nitrate according to the following equation:

[tex]Cu + 4HNO_3 --- > Cu(NO_3)_2 + 2H_2 +2NO_2[/tex]

The mole ratio of copper the nitric acid is 1:4.

I g of copper is equivalent to:

mole = mass/molar mass

         = 1/64

          = 0.016 mol

The equivalent mol of the nitric acid would be: 0.016 x 4 = 0.064 mol

Recall that molarity is the ratio of the number of moles of solutes and the volume of the solution in liters.

Thus, volume = mole/molarity.

Volume of 0.064 mol nitric acid = 0.064/15.8

                                                     = 0.004 liters

0.004 liters = 4 mL

Thus, the volume of the concentrated nitric acid that will be required to completely react with 1.00 grams of copper would be 0.004 liters or 4 mL.

More on stoichiometric problems can be found here: https://brainly.com/question/14465605

#SPJ1

The 32.9 % of the compound has decomposed after 3.45 minutes in the first order decomposition reaction.

In the first order, For decomposition we use the formula

          A(t) = A0e-kt

    where,

              A0 is the initial amount of decomposed substance at t = 0,

               k is the constant of decay

               t is the time elapsed

              A(t) is the amount after time t.

First order reaction is one in which the rate of reaction is proportional to the concentration of the reactant. It doubling the concentration doubles the reaction rate. A first-order reaction can have one or two reactants as in the case of the decomposition reaction. The percentage of decomposed compound left after a time t is, [A(t)], divided the the initial amount, [A0], time 100, or

            [A(t)] =  A/A0*100

A = A0e-kt

A/A0 = e-0.00299t, [k = 0.00299, divide both sides by A0]

A/A0 = e-0.00299*372, [t = 6.2 min*(60 sec/ 1 min) = 372 sec]

A/A0 = 32.9%

To learn more about First Order Decomposition Reaction please visit:

https://brainly.com/question/18802932

#SPJ4

Answer:

Therefore, the correct answer is D: CH3COONA, C6H12O6, and C₂H5OH all exist in aqueous solutions in the form of molecules.

Explanation:

All of the substances listed exist in aqueous solutions in the form of molecules.

Aqueous solutions are solutions in which the solvent is water. Substances in aqueous solutions can exist as molecules, ions, or a combination of both.

C6H12O6, also known as glucose, exists as a molecule in an aqueous solution.

C₂H5OH, also known as ethanol, exists as a molecule in an aqueous solution.

K3PO4, also known as potassium phosphate, exists as ions in an aqueous solution. The potassium cation (K+) and phosphate anion (PO4^3-) are separate ions in solution.

CH3COONa, also known as sodium acetate, exists as ions in an aqueous solution. The sodium cation (Na+) and acetate anion (CH3COO^-) are separate ions in solution.

The electrons from the valence sublevel are lost when calcium ionises to produce a calcium ion. Since calcium belongs to Group 2 on the periodic table, its outer shell contains two electrons .

The losing these two valence electrons will be easier for a calcium atom than receiving six additional electrons to complete a full outer shell. As a result, Ca2+ is the most stable calcium ion to form. When calcium turns into an ion, it loses two produce electrons. The Ions always unite in quantities that exactly balance out the positive and the negative charge when they form an ionic bond.

To learn more about electrons, click here.

https://brainly.com/question/1255220

#SPJ4