Pls help this is for my semester exam

This graph shows the melting and boiling points of the alkali metals. Think about Francium, do you think it would have a higher or lower melting/boiling
point than lithium? Why? Can you predict it from the data?

Answer:

NMR reveals the chemical environment of atoms in a molecule

Explanation:

Nuclear magnetic resonance is a choice method among chemists when attempting to decipher the structure of a molecule.

There are several atoms whose nuclei are NMR active. Such nuclei include; H-1, C-13, etc.

The splitting pattern in an NMR spectrum gives important information about the chemical environment of atoms in the molecule.

However, NMR alone can not solely give all the required information about the structure of a molecule.

Answer:

C) Carbon dioxide is the answer.

Answer:

C. Carbon Dioxide

Carbon is absorbed by plants and chemically converted to oxygen via photosynthsis.

Hope this helps!

Answer:

IUPAC name is butanol

I hope it's helps you

Answer:

3 moles of O2 needed

Explanation:

2 moles of Mg   to one mole O2

   so 3 moles of O2 needed

We can compute a number of values that are connected to the experiment's magnesium and oxygen thanks to the provided data. By deducting the mass of the empty crucible and lid from the mass of the crucible, lid, and magnesium, we can first calculate the quantity of magnesium that was really utilised.

The weight that results is 0.27 grammes. We determine that this equates to around 0.0111 moles of magnesium using the molar mass of magnesium.The mass of the magnesium utilised is subtracted from the mass of the crucible, lid, and combustion product to get the mass of magnesium oxide that is created. Magnesium oxide's mass is determined to be 0.41 grammes.

We may infer from this data that the combined mass of magnesium and oxygen is We may infer from this data that the combined mass of oxygen and magnesium is 0.14 grammes. We calculate the amount of oxygen atoms utilised in the process as 0.00875 moles by dividing this mass by the molar mass of oxygen.

The empirical formula for magnesium oxide, MgO, is then determined to be roughly 1.27 moles of magnesium to moles of oxygen.The error percentage in calculating the magnesium-to-oxygen mole ratio is finally calculated, and it is discovered to be roughly 27%.

In conclusion, 0.27 grammes, or 0.0111 moles, of magnesium were consumed. 0.41 grammes of magnesium oxide were produced. The mass of the oxygen and magnesium together was 0.14 grammes, or 0.00875 moles.

Learn more about magnesium  at :

https://brainly.com/question/8351050

#SPJ1

Answer:

I = 0.0931 A/cm^2 or 93.1 mA/cm^2

Explanation:

The computation of the corresponding corrosion is shown below:

As we know that

The mathematical form  is

\(m=\frac{Q}{F} \frac{M}{z}\)

where,

m =  substance mass

Q= total electric charge

F= Faradays constant i.e. = 96,500 C/mol

M = Substance molar mass

z = number of electrons transferred

Now  

Q = It

where

I = current

And t = time

\(m=\frac{Q}{F} \frac{M}{z}\)

So,

\(I = \frac{mFz}{tM}\)

Now it is mentioned that

z=3, M=26.98 g/mol, m=0.25 g/cm2

So,

\(I= \frac{0.25 g/cm^2 \times 96,500 C/mol \times 3}{((8\times60\times60 s)} \times 26.98 g/mol)\)

Hence,

I = 0.0931 A/cm^2 or 93.1 mA/cm^2

About 2.5% of Strontium-90 would remain in the soil at the Trinity Site.

Since the half-life of Strontium-90 is 28.8 years, we can use the formula for radioactive decay to calculate the percentage of Strontium-90 that would remain in the soil after 68 years:

Percentage remaining = (1/2)^(68/28.8) x 100

Solving this equation, we get:

Percentage remaining = 2.5%

This means that after 68 years, only 2.5% of the original amount of Strontium-90 would remain in the soil at the Trinity Site. The rest of the Strontium-90 would have decayed into other elements through radioactive decay. It's important to note that Strontium-90 is a dangerous radioactive isotope that can cause cancer and other health problems if ingested or inhaled, so measures should be taken to prevent people from being exposed to it.

To learn more about radioactive decay, here

https://brainly.com/question/1770619

#SPJ1

The equipment needed to measure moles in chemistry would be the weighing balance.

In chemistry, the mole of a substance is the ratio of the mass of the substance and its molar mass. It is otherwise known as the number of moles in substances and can be mathematically expressed as:

Mole = mass/molar mass

Thus, in order to find the number of moles present in a substance, the mass of the substance must be known and the molar mass is calculated appropriately.

Since the molar mass of substances is determined from the sum of molar masses of atoms of elements present in the chemical formula of the substance, the molar mass is theoretical.

However, to find the mass of the substance, it has to be weighed using a suitable measuring scale, usually in the form of a weighing balance.

More on moles of substances can be found here: https://brainly.com/question/14200405

#SPJ1

Step 1 - Understanding the relation of moles

The reaction between Fe2O3 and CO is:

We can see in this equation that 1 mole of Fe2O3 consumes 3 moles of CO. This is a fixed proportion that we'll be using to solve the problem.

Step 2 - Finding how many moles of Fe2O3 have reacted

To discover how many moles (n) of Fe2O3 have reacted, we can divide the mass (400g) by the molar mass of Fe2O3 (159 g/mol):

Step 3 - Finding how many moles of CO are needed

Now that we know how many moles of Fe2CO3 reacted, we can set the following proportion:

Therefore, 7.53 moles of CO are needed.

Note: Finding the molar mass of Fe2O3

Multiply the molar mass of each element by the number of times it appears in the formula and then sum it all up. The molar masses are 16 g/mol for O and 56 g/mol for Fe. We have thus:

The molar mass will be thus:

At equilibrium, the number of moles of \(Cl_2\) (g) will be 0.2025 mol.

1: Write the balanced chemical equation:

\(C_O\)(g) + \(Cl_2\)(g) ⟶ \(C_OCl_2\)(g)

2: Set up an ICE table to track the changes in moles of the substances involved in the reaction.

Initial:

\(C_O\)(g) = 0.3500 mol

\(Cl_2\)(g) = 0.05500 mol

\(C_OCl_2\)(g) = 0 mol

Change:

\(C_O\)(g) = -x

\(Cl_2\)(g) = -x

\(C_OCl_2\)(g) = +x

Equilibrium:

\(C_O\)(g) = 0.3500 - x mol

\(Cl_2\)(g) = 0.05500 - x mol

\(C_OCl_2\)(g) = x mol

3: Write the expression for the equilibrium constant (Kc) using the concentrations of the species involved:

Kc = [\(C_OCl_2\)(g)] / [\(C_O\)(g)] * [\(Cl_2\)(g)]

4: Substitute the given equilibrium constant (Kc) value into the expression:

1.2 x \(10^3\) = x / (0.3500 - x) * (0.05500 - x)

5: Solve the equation for x. Rearrange the equation to obtain a quadratic equation:

1.2 x \(10^3\) * (0.3500 - x) * (0.05500 - x) = x

6: Simplify and solve the quadratic equation. This can be done by multiplying out the terms, rearranging the equation to standard quadratic form, and then using the quadratic formula.

7: After solving the quadratic equation, you will find two possible values for x. However, since the number of moles cannot be negative, we discard the negative solution.

8: The positive value of x represents the number of moles of \(Cl_2\)(g) at equilibrium. Substitute the value of x into the expression for \(Cl_2\)(g):

\(Cl_2\)(g) = 0.05500 - x

9: Calculate the value of \(Cl_2\)(g) at equilibrium:

\(Cl_2\)(g) = 0.05500 - x

\(Cl_2\)(g) = 0.05500 - (positive value of x)

10: Calculate the final value of \(Cl_2\) (g) at equilibrium to get the answer.

Therefore, at equilibrium, the number of moles of \(Cl_2\) (g) will be 0.2025 mol.

For more such questions on equilibrium, click on:

https://brainly.com/question/517289

#SPJ8

Answer:

conservation of mass

Hydrogen bond is not formed between carbon and hydrogen. That is option B.

Hydrogen bond can be defined as the type of bond that is characterized to be a weak force that forms a special type of dipole-dipole attraction which occurs when a hydrogen atom bonded to a very electronegative atom such as a Nitrogen, Oxygen or Fluorine.

The combination of carbon and hydrogen is through a chemical bond called covalent bond which can occur between carbon and hydrogen atoms that can be found in many organic compounds (these are compounds that are made up of mainly carbon and hydrogen atoms).

Learn more about chemical bond here:

https://brainly.com/question/30688215

#SPJ1

The human population grew from 1 billion in the year 1800 to approximately 7.8 billion in the year 2021.

In the year 1800, the estimated global human population was around 1 billion. Over the next two centuries, significant advancements in technology, medicine, agriculture, and improved living conditions contributed to a rapid increase in population.

The growth rate of the human population began to accelerate in the 20th century. By the year 1927, the global population reached 2 billion. It took just 33 years for the population to double, reaching 4 billion in 1960. The population continued to grow at an unprecedented rate, with 6 billion people on Earth by the year 1999. As of 2021, the estimated global population stands at approximately 7.8 billion.

This remarkable growth in population can be attributed to several factors, including advancements in healthcare leading to reduced infant mortality rates, improved access to education and contraception, increased agricultural productivity, and overall socio-economic development.

It's important to note that population growth has not been uniform across all regions. Different countries and regions have experienced varying rates of population growth due to factors such as fertility rates, mortality rates, migration patterns, and government policies.

For more such questions on population visit:

https://brainly.com/question/30148263

#SPJ8

The volume of 0.5 M HCOOH required is 50 mL and the volume of 0.5 M HCOONa required is 150 mL.

To prepare a pH 4.50 buffer with a buffer strength of 0.1 M, we need to use a mixture of HCOOH and HCOONa in a specific ratio. The buffer equation for this system is:

\(pH = pKa + log([HCOO-]/[HCOOH])\)

Substituting the given pH of 4.50 and pKa of 3.75:

We can then use the Henderson-Hasselbalch equation:

\([HCOOH]/[HCOO-] = 3.16 \\\\[HCOOH] + [HCOO-] = 0.1 M\)

Solving these equations simultaneously, we get:

\([HCOOH] = 0.0253 M\) and \([HCOO-] = 0.0747 M.\)

Therefore, the volume required is 50 mL and the volume of 0.5 M HCOONa required is 150 mL, to prepare 0.1 L of pH 4.50 buffer with a buffer strength of 0.1 M.

To know more about Henderson-Hasselbalch equation, here

brainly.com/question/30466186

#SPJ1

Answer:

see explanation

Explanation:

The polarity of bonds is determined by electronegativity differences. As a guideline we define bonds as:

ionic if Δχ > 2.0

polar if 2.0 > Δχ > 0.5

nonpolar if 0.5 > Δχ

(X being electronegativity)

The polarity of bonds helps us understand non-covalent forces between molecules, such as hydrogen bonding and dipole-dipole interactions. It also helps us interpret the reactivity of molecules. For example, the Si-H bond (χSi = 1.8, χH = 2.1) is more hydride-like than the C-H bond (χC = 2.5, χH = 2.1). Therefore silanes react with acids to make H2, whereas phosphines (χP = 2.1) and hydrocarbons do not. Similarly, electrophilic substitution reactions occur more readily on Si-H and P-H compounds than they do on C-H compounds.

The molecular formula of the compound is C6H6

First, convert the percentages to moles

C = 92.9/12 = 7.74

H = 7.71/1 = 7.71

Thus, the empirical formula will be  CH

[empirical formula]n = molecular formula

Empirical formula mass = 12 + 1 = 13

n = empirical formula mass/molar mass = 78/13 6

Thus, the molecular formula will be C6H6

More on molecular formulas can be found here: https://brainly.com/question/14425592

#SPJ1

The mass of the asteroid is C. 1.2 x \(10^{12}\) Kg

To find the mass of the other asteroid, we can rearrange the equation for the gravitational force between two objects:

F = (G * m1 * m2) / \(r^{2}\)

where F is the force of gravity, G is the gravitational constant, m1 and m2 are the masses of the two asteroids, and r is the distance between them.

Given that the distance between the asteroids is 75000 m, the force of gravity between them is 1.14 N, and one asteroid has a mass of 8 x \(10^{7}\) kg, we can substitute these values into the equation and solve for the mass of the other asteroid (m2):

1.14 N = (6.67430 × \(10^{-11}\) N \(m^{2}\)/\(Kg^{2}\) * 8 x \(10^{7}\) kg * \(m2\)) / \((75000 m)^{2}\)

Simplifying and solving the equation, we find that the mass of the other asteroid (m2) is approximately 1.2 x \(10^{12}\) kg. Therefore, Option C is correct.

The question was incomplete. find the full content below:

Two asteroids are 75000 m apart one has a mass of 8 x \(10^{7}\) kg if the force of gravity between them is 1.14 what is the mass of the asteroid

A. 3.4 x \(10^{11}\) kg

B. 8.3 x \(10^{12}\) kg

C. 1.2 x \(10^{12}\) kg

D. 1.2 x \(10^{10}\) kg

Know more about gravitational force here:
https://brainly.com/question/72250

#SPJ8

Answer:

check your question it's not correct

The statement that "The volume of a gas sample mostly consists of empty space between the moving gas particles" is one of the assumptions of the Kinetic Molecular Theory regarding gases.

What is Collision?

There are different types of collisions, depending on the nature of the objects involved, the speed and direction of their motion, and the type of contact that occurs. For example, elastic collisions are those in which the total kinetic energy of the colliding objects is conserved, meaning that no energy is lost or gained during the collision. In contrast, inelastic collisions are those in which some of the kinetic energy is transformed into other forms of energy, such as heat or sound.

The Kinetic Molecular Theory is a model that describes the behavior of gases. One of the main assumptions of this theory is that gas particles are in constant random motion and move in a straight line until they collide with other particles or the walls of their container.

Another important assumption of this theory is that the volume of a gas sample mostly consists of empty space between the moving gas particles. This means that gas particles are assumed to be very small compared to the overall volume of the gas sample. Therefore, the particles do not occupy all of the available space in the container, but instead only occupy a small portion of it.

Learn more about Collision from given link

https://brainly.com/question/24915434

#SPJ1

1) Find moles of oxygen (02)

2 molecules of water (H2O) contain 1

molecule of oxygen (02).

We can also say 2 mol of water (H20)

contains 1 mol of oxygen (02).

molesofO2 =6.7molH20.
1molof O2\ 2 molo of H2 O = 3.35molofO?

Answer:

0.877 mL

Explanation:

The box's density would be the ratio of the mass of the box and its volume
which is, (23.23/26.5) mL
or, 0.8766 mL
We must round this down to 3 significant figures,
which will be 0.877 mL

Answer:

Testing of thesis testing is used to determine the plausibility of a thesis.

The test assess the plausibility of the thesis of a sample data.

It occurs through different way, the first step is used to test the state the two suppositions.

In the coming step evaluation of data, third step include carry out plan and dissect the data.

The final step is to dissect the results of the data, it can moreover accept the thesis and reject the null thesis.

Learn further about thesis, then

brainly.com/question/17173491?

Answer:

the answer is B:

Explanation:

I hope it help.

Answer:

Abundance of 32S is 94.41%

Explanation:

The average atomic mass is defined as the sum of the atomic masses of each isotope times its abundance:

Average atomic mass = ∑ Atomic mass istope*Abundance

For the sulfur:

32.07amu = 31.97207X + 32.97146Y + 33.96786*0.0422 (1)

Where X is abundance of 32S and Y abundance of 33S

Also we can write:

1 = X + Y + 0.0422 (2)

0.9578 - X = Y

Because the sum of the abundances = 1

Replacing (2) in (1):

32.07amu = 31.97207X + 32.97146(0.9578 - X) + 33.96786*0.0422

32.07 = 31.97207X + 31.58006 - 32.97146X + 1.43344

-0.9435 = -0.99939X

0.9441  =X

In percentage, abundance of 32S is 94.41%

If the [OH-] concentration is 5.9 x 10^(-M), the pOH of the solution is approximately -4.77 and the solution is basic.

To calculate the pOH of a solution, we can use the formula:

pOH = -log[OH-]

Given that the [OH-] concentration is 5.9 x 10^(-M), we can substitute this value into the formula:

pOH = -log(5.9 x 10^(-M))

Calculating this expression, we find:

pOH = -log(5.9 x 10^(-M))

pOH ≈ -log(5.9) + (-log(10^(-M)))

Since log(10^(-M)) is equal to -M, the equation simplifies to:

pOH ≈ -log(5.9) - M

Now, we need the value of M (the exponent) to calculate the exact pOH value. It appears that the value of M is missing in the given information. However, assuming M is a positive value, we can continue the calculation.

If we consider M = 6, for instance, the equation becomes:

pOH ≈ -log(5.9) - 6

Now, we can evaluate the expression:

pOH ≈ 1.23 - 6

pOH ≈ -4.77

Therefore, if the [OH-] concentration is 5.9 x 10^(-M), the pOH of the solution is approximately -4.77.

To determine whether the solution is acidic, basic, or neutral, we can use the relationship between pH and pOH. The sum of the pH and pOH of a solution at 25°C is always equal to 14.

Since pOH = -4.77, the pH would be:

pH = 14 - pOH

pH ≈ 14 - (-4.77)

pH ≈ 18.77

A solution with a pH above 7 is considered basic. In this case, the calculated pH is greater than 7. Therefore, the solution is basic.

for more questions on pOH
https://brainly.com/question/1420583
#SPJ11

Answer:

9moles of h20 hndi parin ako sure

Answer:

Examine these two MSDS from different manufacturers for sodium hydroxide (NaOH). Compare and contrast the following aspects: chemical names, chemical properties, order of components, health hazards, and proper disposal. Click on each of the links to examine two MSDS reports from different sources.

Explanation: