Chemistry College

## Answers

**Answer 1**

1 mile = 1609.344 meters

1 hour = 3600 seconds 345.48 miles per hour x 1609.344

meters/mile x 1hour/3600seconds = 154.44 meter per second~~ANSWERR

## Related Questions

A 29.00 mL sample of an unknown H3PO4 solution is titrated with a 0.130 M NaOH solution. The equivalence point is reached when 27.73 mL of NaOH solution is added.

### Answers

I am first assuming that you want the molarity of the acid. Use the formula which is the titration formula. M is molarity (a is of acid and b is of base) and V is volume in mL (a is of acid and b is of base). Plugging in gives us. Solving gives us

What is the pH of a solution with a hydronium ion concentration of 5.6 x 10^-9

### Answers

Recall that the formula for pH is. The brackets represent the concentration of the hydronium or H+ ions. Plug into the calculator and get your answer as 8.25

Answer:

9.28

Explanation:

The moles of oxygen(o) in 2.0 moles of Al(OH)3 is

A. 1.0 B.2.0 C. 3.0 D. 4.0 E.6.0

### Answers

E: 6 moles of oxygen because the subscript 3 makes 3 moles of oxygen then multiply it by the coefficient 2, therefore making 6 moles of oxygen.

a normal hemoglobin concentration in the blood is 15g/100ml of blood how many kilogram of hemoglobin are in a person who has 5.5 l of blood

### Answers

Answer:

there are 0.825 kg in 5.5 l of blood

Explanation:

First, we have to convert L into mL so we work with the same units

Using a rule of three we have:

15 g of hemoglobin ------> 100 mL of blood

x ------> 5500 mL of blood

As the answer must be in kilogram we must convert grams into kilograms:

Using stoichiometry:

5.5 L of blood x (1000 mL/1L) x (15 g/100 mL) x (1 kg/1000 g) = 0.825 kg

Calculate the molecular weights for NH3 and SF6.

### Answers

Hi there,

NH3 has the weight of 17.03 grams, and SF6 has the weight of 146.06 grams

so in total, there is 163.09 grams

Hope this helps :P

A chemist wants to make 6.5 L of a .350M CaCl2 solution. What mass of CaCl2(in g) should the chemist use?

### Answers

First M stands for Molarity which is (moles of solute) / (Liters of solution). we also know that moles = (mass) / (molar mass). so we can form some equations here. We know:

Molarity (M) = moles (mol) / Liters (L)

moles (mol) = (mass) / (molar mass)

we can substitute the (mass) / (molar mass) for (moles) and get:

M = [(mass) / (molar mass)] / Liters

we can now isolate mass and get

M * Liters * molar mass = mass

now we need to find the molar mass of CaCl2 which is 110.98 g/mol

plug the values in and get

.350M * 6.5L * 110.98 g/mol = mass

mass = 252.4795g however the 6.5L has only 2 sig figs so i would say

mass CaCl2 = 2.5 * 10 ^2 g

Known: M = 350 M

Mol = 6.6 L

Molar mass of CaCl2 = 110.98 g / ml

Asked: Mass of CaCl2?

Answer: First, we will use the formula:

M = {(mass) / (molar mass)} / mol

=> mass = M x mol x molar mass

Second, enter a known value

mass = 350 M x 6.5 L x 110.98 g / mol

CaCl2 mass = 2.5 x 10 ^ 2 g

So, the mass of CaCl2 is 2.5 x 10 ^ 2 g.

Further Explanation

Molarity is a quantity that can express the number of moles of solute in each unit volume of solution. The unit of molarity is the molar (M) which is equal to mol/liter. If there are (n) moles of compounds dissolved in (V) liters of a solution.

A mole is a mathematically obtained unit, involving several other units such as the relative molecular mass, and the average atomic mass. A mole is defined as the number of particles contained in a particular substance where the number is equal to the number of atoms contained in 12.00 grams of C-12 atoms. C-12 is a carbon isotope that has a definitive standard atomic weight of 12. Therefore, the mass of this carbon isotope has an exact weight of 12 grams. The use of carbon as a basis for determination because carbon is the element most often and easily found in nature.

The chemical reaction is the event of chemical change from substances that react (reactants) into substances that result from reactions (products). In chemical reactions, new substances are always produced with new properties. Chemical reactions are written using the element symbol. Let's look at how to express a reaction using symbols.

Learn more

definition of Molarity brainly.com/question/12264701

definition of A mole brainly.com/question/12264701

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Grade: College

Subject: Chemistry

keywords: Molarity

If a 375 mL sample of water was cooled from 37.5 degrees Celsius to 0 degrees Celsius , how much heat was lost (in joules)

### Answers

Explanation:

It is given that volume is 375 mL and is 37.5 degree celsius.

First, we will calculate the mass of sample of water as it is known that density of water is 1 .

Hence, Density =

1 =

mass = 375 g

Therefore, formula to calculate heat loss will be as follows.

q = mC

where q = heat lost or absorbed

m = mass

C = specific heat of water = 4.186 J/g

= change in temperature

Hence, we will calculate value of heat lost as follows.

q = mC

= 375 g × 4.186 J/g × ( 0 - 37.5) degree celsius

= - 58865.62 joules

Thus, we can conclude that heat lost is -58865.62 joules.

Please, you have to apply the formula below:Q=c∗m∗Δtwhere Q is the energy lost, c is the specific heat of water, m is the mass of water involved, so m=3.75 *10^-1 Kg c=4,184 J/(Kg*°C) delta t=37.5 °C

Taking density of water as 1000kg/m3. Mass of water would be 0.375kg. So, heat lost would beH=mCDeltaTH=0.375*4184*37.5 = 58837.5J

if 6.02 x 10 23 molecules of N2 react according to the equation N2 +3h2 2NH3, the total number of molecules of NH3 is produced is ?

### Answers

Answer:

Explanation:

Hello,

In this case, we apply a set of proportional factors to provide the total number of molecules of ammonia that are produced, taking into account the 1 to 2 relationship between nitrogen and ammonia (based on the undergoing chemical reaction) and the fact that one mole of substance is related with the Avogadro's number in terms of molecules in this case, in such a way, we apply the shown below procedure:

Best regards.

N2+3H2---->2NH3

6.02×10 23 equals to one mole. if one mole of N2 enters reaction 2NH3 isproduced , so 2×6.02 10 23

12.04 × 10 23

How many atoms are in 167 g of calcium?

### Answers

1) Divide grams of Ca by the atomic weight of Ca. This gives moles of Ca.

2) Multiply moles of Ca by Avogadro's Number (6.022 x 10^23 atoms mol^-1). This yields the answer you seek

Suppose that a solution containing 3.50 grams of sodium phosphate (Na3PO4) is mixed with a solution containing 6.40 grams of barium nitrate (Ba(NO3)2). Calculate the theoretical yield of barium phosphate (Ba3(PO4)2) during this reaction. 2Na3PO4 + 3Ba(NO3)2 Ba3(PO4)2 + 6NaNO3

### Answers

We are given

3.5 g Na3PO4

6.4 g Ba(NO3)2

and the reaction

2 Na3PO4 + 3 Ba(NO3)2 ----> Ba3(PO4)2 + 6 NaNO3

Convert the masses to moles using molar masses of N3PO4 and Ba(NO3)2

Next, determine the limiting reactant by using stoichiometry:

moles Na3PO4 (1 / 2) = moles Ba3PO4

moles Ba(NO3)2 (1 /3) = moles Ba3PO4

The lower amount of moles will be maximum and the reactant is limiting

Convert moles to mass and divide it by the mass of the limiting reactant to get the yield.

A moon rock collected by a U.S. Apollo mission is estimated to be 4.20 billion years old by uranium/lead dating. Assuming that the rock did not contain any lead when it was formed, what is the current mass of 206Pb per 1.305 g of 238U in the rock? The half-life of 238U is t1/2 = 4.47 × 109 years.

### Answers

The current mass of 206Pb per 1.305g of 238U in the rock is 1.037 grams

To be able to solve this question, we need to know the rate constant and the half-life of the radioactive isotope.

What is the rate constant?

From the first order of kinetics, the rate constant is the proportionality constant in relation to the half-life.

It can be expressed by using the formula:

Now, from the parameters given:

- The mass of 238U = 1.350 g
- Suppose we assume that the mass of 206Pb = x

Therefore, the equation for the decay constant can be computed as:

x = 2.503 - 1.305

x = 1.198

Now, the mass of the 206Pb is calculated as:

= 1.037 grams

Learn more about rate constant here:

brainly.com/question/26127112

Answer : The current mass of 206-Pb per 1.305 g of 238-U in the rock is, 0.54 grams.

Explanation :

This is a type of radioactive decay and all radioactive decays follow first order kinetics.

To calculate the rate constant, we use the formula :

Now we have to calculate the moles of 238-U.

Now we have to calculate the amount left.

Expression for rate law for first order kinetics is given by :

where,

k = rate constant

t = time taken for decay process

a = initial amount or moles of the reactant

a - x = amount or moles left after decay process

Putting values in above equation, we get:

Now we have to calculate the decomposed moles of uranium.

As we know that,

1 mole of is produced by 1 mole

The decomposed moles of Pb =

Now we have to calculate the current mass of 206-Pb per 1.305 g of 238-U in the rock.

Therefore, the current mass of 206-Pb per 1.305 g of 238-U in the rock is, 0.54 grams.

How many tons of zinc can be obtained from 976 tons of zinc ore that is 78.0% zinc carbonate?

### Answers

Answer : The amount of zinc obtained can be 396.9 tons.

Explanation :

First we have to calculate the amount zinc carbonate in 976 tons.

Amount of zinc carbonate =

Now we have to calculate the percentage of zinc in zinc carbonate.

As we know that,

Atomic mass of zinc = 65.38 g

Atomic mass of zinc carbonate = 125.38 g

Now we have to calculate the amount of zinc in 761.28 tons.

Amount of zinc =

Therefore, the amount of zinc obtained can be 396.9 tons.

First, calculating the amount of zinc carbonate by multiplying the given mass of the ore by the percent zinc carbonate.

mass of zinc carbonate = (976 tons)(0.78)

= 761.28 tons

Then, calculate for %Zn in zinc carbonate

%Zn = ((65.38) / (125.39)) x 100%

% Zn = 52.141%

tons of Zn from the sample,

mass of Zn = (761.28 tons)(0.52141)

= 396.94 tons Zn

How many sulfide ions are present in 23.5g of Sb2S3

### Answers

Answer: The number of sulfide ion are,

Explanation : Given,

Mass of = 23.5 g

Molar mass of = 339.7 g/mol

First we have to calculate the moles of

Now we have to calculate the moles of sulfide ion.

In , there are 2 moles of ion and 3 moles of ion.

As, 3 mole of sulfide ion contains sulfide ion

So, 0.0692 mole of sulfide ion contains sulfide ion

Thus, the number of sulfide ion are,

You can figure it out by doing dimensional analysis and plugging in the information you're given and then using the answer to your dimensional analysis to do percent composition and then your answer to that will be your final answer.

A 50g ice cube at 0 degrees celcius is added to a glass containing 400g of water at 45 degrees celcius. What is the final temperature of the system? You may assume that no heat is lost to the surroundings.

### Answers

In a system, heat that is gained and lost should be conserved. We calculate as follows:

Heat from phase change + sensible heat from the change in tempeture of the ice = sensible heat from the change in temperature of water

mH(fusion) + mCpΔT = mCpΔT

.05 (335) + .050(4.184)( T - 0) = .4 (4.184)(45 - T)

T = 34.8°C

Calculate [H3O+] for the 0.10 M CH3COOH solution which has a pH = 2.88. -What percent of the weak acid is dissociated?

### Answers

The concentration of the hydronium ion can be calculated from the pH as follows:

pH = -log[H3O]

2.88 = -log [H3O]

[H3O] = 1.32x10^-3 M

The percent dissociation can be calculated as follows:

% dissociation = 1.32x10^-3 / 0.10 x100 = 1.32%

Equilibrium constant of: O2(g)+2H2O(l)+2Sn2+(aq)→4OH−(aq)+2Sn4+(aq)

### Answers

Equilibrium constant of a reaction is the ratio of the product of the concentration of the products in equilibrium over the product of the concentration of the reactants in equilibrium. For this case,

K = [OH]^4 [Sn4+]^2 / [O2] [H2O]^2[Sn2+]^2

How many formula units are contained in 23.5 g of Sb2S3

### Answers

The molar mass of Sb2S3 is approximately equal to 339.7 g/mol. We calculate the number of moles of Sb2S3 by dividing the given mass by the molar mass.

n = 23.5 g / (339.7 g/mol)

n = 0.0692 mols

To calculate for the number of formula units, we multiply the number of mols by the Avogadro's number,

number of formula units = (0.0692 mols)(6.022 x 10^3)

= 4.167 x 10^22 formula units

Answer: The number of formula units in given amount of are

Explanation:

To calculate the number of moles, we use the equation:

Given mass of = 23.5 g

Molar mass of = 339.7 g/mol

Putting values in above equation, we get:

According to mole concept:

1 mole of a compound contains number of formula units

So, 0.069 moles of will contain = number of formula units

Hence, the number of formula units in given amount of are

If a 375ml sample of water was cooled from 37.5 C to 0 C, how much heat was lost in joules?

### Answers

To answer this item, we use 1 g/mL as the conventional density of water at any temperature. Thus, the amount of water in grams is,

m = (375 mL) x (1g/mL) = 375 g

Then, we use the equation

H = mcpdT

where m is the mass, cp is the specific heat of water (4.18 J/g°C), and dT is the temperature difference. Substituting,

H = (375 g)(4.18 J/g°C)(0° - 37°)

= -57997.5°C

Therefore, the amount of heat released is equal to 57,997.5°C.

Balance each of the following redox reactions occurring in basic solution

### Answers

When balancing redox reactions in basic solutions, first, we need to balance the number of oxygen atoms by adding OH- ions to either side. Then, we add H+ ions to balance the number of hydrogen atoms. After it is balanced, we combine the H+ and OH- in either side into H2O. Hope this helps.

Write balanced complete ionic equation for MgS(aq)+CuCl2(aq) = CuS(s)+MgCl2(aq)

### Answers

The balanced chemical ionic equarion of MgS(aq)+CuCl2(aq) = CuS(s)+MgCl2(aq) would be as follows:

Mg2+ + S2- + Cu 2+ + 2 Cl- ==> CuS + Mg2+ + 2 Cl-

Therefore, the net equation would be:

Cu 2+ + S 2- ===> CuS

Hope this helps.

Answer : The net ionic equation will be,

Explanation :

In the net ionic equations, we are not include the spectator ions in the equations.

Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.

The given balanced ionic equation will be,

The ionic equation in separated aqueous solution will be,

In this equation, are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,