Answer:
56.0kJ/mol
Explanation:
The reaction of NaOH with HCl is:
NaOH + HCl → H₂O + NaCl + ΔH
Where ΔH is the heat of reaction that is released per mole of reactants,
The moles that reacts are:
100mL = 0.1L * (1mol / L) = 0.1 moles reacts
To find the heat released in the coffee cup calorimeter, you use the equation:
Q = m×ΔT×C
Where Q is heat released,
m is mass of the solution
ΔT is change in temperature (Final temperature - Initial temperature)
C is specific heat of the solution (4.18J/g°C)
Mass of the solution is:
100mL + 100mL = 200mL
Density of the solution is 1.0g/mL. The mass is 200g
Change in temperature is 31.3°C - 24.6°C = 6.7°C
Replacing:
Q = m×ΔT×C
Q = 200g×6.7°C×4.18J/g°C
Q = 5601.2J
This is the heat released per 0.1mol. The heat released per mole (Enthalpy change for the neutralization of HCl by NaOH is:
5601.2J / 0.1 moles = 56012J / mol =
56.0kJ/mol
convert 6.8 × 10^2 to standard notation.
Answer:
680
Explanation:
Move the decimal 2 to the right.
When a number is written using only the digits of the number, that is considered standard notation. 6.8 × 10² is converted into standard notation by shifting two decimal to the right side, then it became 680.
What is standard notation ?A form of writing a certain number, an equation, or an expression in a way that adheres to set norms is known as a standard notation. For instance, 4,500,000,000 years is how 4.5 billion years is written.
When a number is written using only the digits of the number, that is considered standard notation. Since words are not used in conventional number notation, this is the way that numbers are typically written.
The stages to writing a number in its standard form are as follows: Write the first digit of the supplied number in step one. Step 2: After the first number, add the decimal point. Step 3: Next, count how many digits there are in the supplied number after the first one and express that number as a power of 10.
Thus, the standard notation is 680.
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Eric's father asked an engineer to survey the field behind their house. He wanted to plant some apple and pear trees there. According to the survey, the field is 38 meters (m) long and 17 meters (m) wide. What is the perimeter of the field in centimeters?
Answer:
P=110 m
Explanation:
Length of the field is 38 m
Breadth of the field is 17 m
We need to find the perimeter of this field. It is in the form of a rectangle. The perimeter of a rectangle is given by :
P=2(l+b)
P=2(38+17)
P=110 m
So, the perimeter of this field is 110 m.
Which statement is false? a) When reactants become products, they do so through an intermediate transition state. b) At equilibrium, equal amounts of products and reactants are present. c) Most biocatalysts are proteins. d) AG is a function of Keq
Answer:
b) At equilibrium, equal amounts of products and reactants are present.
Explanation:
At equilibrium , the ratio of product of concentration of products and product of concentration of reactants is constant .
A + B ⇄ C + D
[C] [ D] / [ A ] [ B ] = Constant
So, the statement ( b ) is false .
All other statements are true .
The [H+] of a solution can be determined from the pH using the equation: [H+] = 10 - pH ... Where: [H+] = hydrogen ion concentration. Note: Write [H+] as [H+]. Capitalization counts. Use the rules for logarithms and exponents to solve for pH in terms of [H+].
Answer:
pH = -log₁₀ [H⁺]
Explanation:
pH is a value in chemistry used in to measure solution trying to determine each quality, purity, risks for health of some products, etc.
As you write in the question, [H⁺] = 10^(-pH)
Using logarithm law (log (m^(p) = p log(m):
log₁₀ [H⁺] = -pH
And
pH = -log₁₀ [H⁺]Answer:
7 (a neutral solution)
Answer: 10-7= 0.0000001 moles per liter
5.6 (unpolluted rainwater)
Answer: 10-5.6 = 0.0000025 moles per liter
3.7 (first acid rain sample in North America)
Answer: 10-3.7 = 0.00020 moles per liter
The concentration of H+ in the Hubbard Brook sample is 0.00020/0.0000025, which is 80 times higher than the H+ concentration in unpolluted rainwater.
Explanation:
plato
Hydrogen reacts with nitrogen monoxide to form dinitrogen monoxide (aughing gas) according to the equation: H2 (9) + 2 NOg) N20() + H20G) Based on the following data: H2 (M) NO (M) Rate (M*s) Trial 1 0.30 0.35 2.835 x 10-3 Trial 2 0.60 0.35 1.134 x 10-2 Trial 3 0.60 0.70 2.268 x 10-2 a. What is the order with respect to H2? b. What is the order with respect to NO? c. What is the rate equation for this reaction? d. Calculate the rate constant for the reaction.
Explanation:
H2 (9) + 2 NOg) N20() + H20G)
H2 (M) NO (M) Rate (M*s)
Trial 1 0.30 0.35 2.835 x 10-3
Trial 2 0.60 0.35 1.134 x 10-2
Trial 3 0.60 0.70 2.268 x 10-2
a. What is the order with respect to H2?
Comparing trials 1 and 2,the concentration of H is doubled and that leads to an increase in the rate of the reaction by a factor of 4. This means the order with respect to H is 2.
b. What is the order with respect to NO?
Comparing trials 2 and 3, the concentration of NO is doubled and that leads to an increase in the rate of the reaction by a factor of 2. This means the order with respect to NO is 1.
c. What is the rate equation for this reaction?
rate = k [H]²[NO]
d. Calculate the rate constant for the reaction.
Taking trial 1;
rate = k [H]²[NO]
2.835 x 10-3 = k (0.30)² (0.35)
k = 90 x 10-3 = 0.09 L2 mol-2 s-1
How would replacing many amino groups with carboxyl groups change the properties of the compound?
Answer:
This replacements will make the compound less basic and more acidic
Explanation:
Replacing amino groups (-NH₂) which act as bases [because of there ability to accept hydrogen ion (H⁺)] with carboxyl group (-COOH) which acts as acid [because of it's ability to donate hydrogen ion (H⁺)] in a compound changes the property of the compound to be less basic and more acidic.
Convert 2.350 km/hour to cm/sec HELP NOW PLEASE!!!! I NEED THE WORK
Answer:
1km/h =27.778cm/s
therefore
if 1km/h=27.778cm/s
2.350km/h=?
cross multiple
2.350km/h X27.778cm/s /1km/h
=65.2783cm/s
the weight of a sack potato in india is 50kgf. will the weight increase or decrease in bhutan. why
Answer:
Assume that the sack was initially close to the sea level. Its weight will increase even though its mass stays the same.
Explanation:
The weight of an object typically refers to the size of the planet's gravitational attraction (a force) on this object. That's not the same as the mass of the object. The weight of an object at a position depends on the size of the gravitational field there; on the other hand, the mass of the object is supposed to be same regardless of the location- as long as the object stays intact.
Let [tex]g[/tex] denote the strength of the gravitational field at a certain point. If the mass of an object is [tex]m[/tex], its weight at that point will be [tex]m \cdot g[/tex].
Indeed, [tex]g \approx 9.81\; \rm N \cdot kg^{-1}[/tex] on many places of the earth. However, this value is accurate only near the sea level. The equation for universal gravitation is a more general way for finding the strength of the gravitational field at an arbitrary height. Let [tex]G[/tex] denote the constant of universal gravitation, and let [tex]M[/tex] denote the mass of the earth. At a distance [tex]r[/tex] from the center of the earth (where
[tex]\displaystyle g \approx \frac{G \cdot M}{r^2}[/tex].
The elevation of many places in Bhutan are significantly higher than that of many places in India. Therefore, a sack of potato in Bhutan will likely be further away from the center of the earth (larger [tex]r[/tex]) compared to a sack of potato in India.
Note, that in the approximation, the value of [tex]g[/tex] is (approximately, because the earth isn't perfectly spherical) inversely proportional to the distance from the center of the planet. The gravitational field strength
On the other hand, the weight of an object of fixed mass is proportional to the gravitational field strength. Therefore, the same bag of potatoes will have a smaller weight at most places in Bhutan compared to most places in India.
Choose all the answers that apply.
Which of the following statements are true?
Ethical scientists make unbiased conclusions.
A dishonest scientst has a lot of integrity.
Confirmation bias is the most common type of bias in science.
Science is based on opinion and subjective evidence.
Bias can be ruled out when similar results are obtained from repeated experiments.
Explanation:
A dishonest scientst has a lot of integrity.
Confirmation bias is the most common type of bias in science.
Answer: ethical scientists make unbiased conclusions, science is based on opinion and subjective evidence, and bias can be ruled out if similar results are obtained from repeated experiments.
Explanation: If you’re a dishonest scientist you don’t have integrity and confirmation bias isn’t the most common type of bias in science
If you know the force applied to an object and measure its acceleration, which equation would you use to calculate the object’s mass? m = Fa m = a F m = a/F m = F/a
Answer: m=F/a
Explanation:
Answer:
d
Explanation:
Classify each substance based on the intermolecular forces present in that substance.A. H2OB. CH4C. CO D. CH3Cl1. Hydrogen bonding, dipole dipole, and dispersion2. Dipole dipole and dispersion only 3. Dispersion only
Answer:
H2O - Hydrogen bonding, dipole dipole, and dispersion
CH4 - Dispersion only
CO - Dipole dipole and dispersion only
CH3Cl - Dipole dipole and dispersion only
Explanation:
Hydrogen bonding can only exist when hydrogen is bonded to a small highly electronegative atom such as oxygen hence hydrogen bonds, dipole interactions and dispersion by are present in water.
CH4 is a nonpolar molecule hence only dispersion forces are present.
CH3Cl and CO both possess dipoles in the molecule hence both dipole interactions and dispersion forces exist in the molecule.
The oxides of nitrogen are very important ingredients in determining urban air pollution. Name each of the following compounds.(a) N2O(b) NO(c) NO2(d) N2O5(e) N2O4
Answer:
(a) N₂O - Dinitrogen monoxide or Dinitrogen (I) oxide
(b) NO - Nitrogen monoxide or Nitrogen (II) oxide
(c) NO₂ - Nitrogen dioxide or Nitrogen (IV) oxide
(d) N₂O₅ - Dinitrogen pentoxide
(e) N₂O₄ - Dinitrogen tetraoxide.
Explanation:
To name each of the compounds,
(a) N2O; It is properly written as N₂O. N₂O is a colorless, sweet tasting gas also known as "laughing gas".
N₂O - Dinitrogen monoxide OR Dinitrogen (I) oxide.
(b) NO; NO is a colorless gas.
NO - Nitrogen monoxide OR Nitrogen (II) oxide.
(c) NO2; It is properly written as NO₂
NO₂ is a reddish-brown gas.
NO₂ - Nitrogen dioxide or Nitrogen (IV) oxide.
(d) N2O5; It is properly written as N₂O₅
N₂O₅ is a white solid.
N₂O₅ - Dinitrogen pentoxide.
(e) N2O4; It is properly written as N₂O₄;
N₂O₄ is a red-brown liquid with an unpleasant smell.
N₂O₄ - Dinitrogen tetraoxide.
A car drives on a road at a constant speed of 50 miles/hour.
The forward force of the car is ________________
the opposing friction and air
resistance forces.
The forward force of the car and the opposing friction and air resistance forces are ____________
( !!
Answer:
It will take the police car 3.5 hours to travel a distance of 175 miles traveling at a rate of 50 miles/hour.
Explanation:
The diameter of an atom is approximately 1 * 10 ^ - 10 * m . What is the diameter in decimeters?
Answer:
[tex]d=1x10^{-9}dm[/tex]
Explanation:
Hello,
In this case, considering that 1 m equals 10 dm, the required diameter of the atom in decimetres is:
[tex]d=1x10^{-10}m*\frac{10dm}{1m} \\\\d=1x10^{-9}dm[/tex]
Best regards.
SN1 reactions of the type, Nu- + RL → Nu–R + L-, are favoured:a. when tertiary substrates are used. b. by using a high concentration of the nucleophile. c. when L- is a strong base. d. by use of an aprotic solvent.
Monobromination of toluene gives a mixture of three bromotoluene products. Draw and name them.
Answer:
o-bromotoluene, m-bromotoluene and p-bromotoluene.
Explanation:
Hello,
In this case, on the attached picture you will find the reaction which yields o-bromotoluene as the first product, m-bromotoluene as the second product and p-bromotoluene as the last one since the substitution could be done at the second (ortho), third (meta) or fourth (para) carbons on the toluene.
Regards.
Calculate the solubility of PbCO3 in water at 25 degree C.
Answer:
2.7 × 10⁻⁷ M
Explanation:
Step 1: Write the reaction for the solution of PbCO₃
PbCO₃(s) ⇄ Pb²⁺(aq) + CO₃²⁻(aq)
Step 2: Make an ICE chart
To relate the solubility of PbCO₃ (S) with its solubility product constant (Ksp) we will make an ICE chart.
PbCO₃(s) ⇄ Pb²⁺(aq) + CO₃²⁻(aq)
I 0 0
C +S +S
E S S
The solubility product constant is:
Ksp = 7.4 × 10⁻¹⁴ = [Pb²⁺] × [CO₃²⁻] = S²
S = √7.4 × 10⁻¹⁴ = 2.7 × 10⁻⁷ M
What are the properties of the aluminum in the
can? Check all that apply.
It conducts electricity well.
It is solid
It is brittle.
It does not react easily with water or air.
It is less dense than water.
Answer:
What are the properties of the aluminum in the can? Check all that apply.
*It conducts electricity well.
*It is solid.
It is brittle.
*It does not react easily with water or air.
It is less dense than water.
Explanation:
a b d
The properties of aluminium (Al) includes electrical conductivity, solid and it does not react easily with water. Therefore, option A, B and D are correct.
What is aluminium?Aluminium is a common metal we use day to day. It is an electropositive element and due to its metallic nature, Al shows electrical and thermal conductivity. Unlike other metals Al can withstand brittleness and it is ductile in nature.
Aluminium easily reacts with oxygen and forms an oxide layer on its surface so that, it can resist attack by other chemical such as acid or bases as well as oil and water. Hence water does not easily react with aluminium.
Therefore, we can say that aluminium is a solid which conduct electricity and not easily reacts with water.
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which of these substances are most likely crystalline solids?
Answer:
diamond
sugar
rubber
salt (NaCl)
wood
ice
flour
Answer:
diamond
sugar
salt
ice
Explanation:
The solubility of oxygen in water A. allows for a greater concentration of O2 in water than in air. B. is responsible for thermoclines. C. is greater in cool liquid water than in warm liquid water. D. isn't significantly dependent on temperature
The ans should be C. ( if i'm not wrong )
This is because the solubility of oxygen increases when temperature in the water is cooler. Cold water can hold more dissolved oxygen than warm water, thus having a higher concentration of oxygen.
Answer:
C. is greater in cool liquid water than in warm liquid water.
Explanation:
For the following, identify the most likely value for x.a. BHx b. CHx c. NHx d. CH2Clx
Given :
a. [tex]BH_x[/tex] b. [tex]CH_x[/tex] c. [tex]NH_x[/tex] d. [tex]CH_2Cl_x[/tex] .
To Find :
Find the most likely vale of x for each one .
Solution :
a . [tex]BH_x[/tex]
Because boron have valency of 3 .
So , x = 3 .
b . [tex]CH_x[/tex]
Valency of carbon is 4 .
x = 4 .
c . [tex]NH_x[/tex]
Valency of nitrogen is 3 .
Therefore , x = 3 .
d . [tex]CH_2Cl_x[/tex]
Now ,we know valency of carbon is 4 and hydrogen is 1 .
Also , two hydrogen are already there .
So , only 2 electrons left to share .
Since , chlorine have valency of 1 .
Therefore , only 2 electrons of chlorine can connect .
x = 2 .
Hence , this is the required solution .
Can someone please help me w these chemistry conversion? 1. The density of Mercury is 13.6 g/mL. What is the volume of mercury, in quarts has a mass of 95.0 ounces? 2. Tetrachloroethylene, also called PERC, has a density of 1.62 g/mL. It was formerly used as a dry cleaning solvent. What is the mass in pounds of PERC contained in a 55.0 gallon drum? 3. Osmium is the most dense element having a density of 22.5 g/cm^3 Calculate the density of osmium in kg/m^3. 4. The density of Iron is 7.50 g/cm^3. What is the mass, in pounds, of a cube of iron that measures 5.00 cm on a side? 5. Lead has a density of 10.5 g/cm^3. What is the diameter of a lead ball that has a mass of 500.0 g? Report answer in cm.
Answer:
1. 0.209quart
2. 743.6pounds
3. 22500kg/m^3
4. 2.07pounds
5. 4.50cm
Explanation:
Note that, these questions are related to density which can be calculated using the formula:
Density (p) = Mass (m) / Volume (v)
However, the units are different for each questions, hence, must be made the same
1. 1 ounce = 28.35 grams
95 ounces will be 95 × 28.35 = 2693.2g
Volume = mass/density
Volume of Mercury= 2693.2/13.6
Volume= 198ml
1 ml = 0.00106quart
198ml = 198 × 0.00106 = 0.209quart
2. 1 gallon = 3785.4ml
55 gallons = 55× 3785.4 = 208197ml
Mass = density × volume
Mass = 1.62 × 208197
Mass = 337,279.14g
1 pounds = 453.592 g
337279.14 g = 337279.14/453.592
Mass = 743.6pounds
3. 1g/cm^3 = 1000kg/m^3
Hence, a density of 22.5g/cm^3 will be 22.5 × 1000 = 22500kg/m^3
4. Volume of a cube of side 5cm each will be 5×5×5 = 125cm^3
Density = 7.50g/cm^3
Mass = Density×volume
Mass in grams = 7.50 × 125
Mass = 937.5grams
1 pound = 453.592 g
Therefore, 937.5g will be 937.5/453.592 = 2.07pounds.
5. Volume = Mass / density
Volume = 500/10.5
Volume = 47.62cm^3
Since a ball is spherical in shape, volume of a sphere (V) = 4/3πr^3
To find radius, we say;
47.62 = 1.33 × 3.142 × r^3
47.62 = 4.179 × r^3
r^3 = 47.62/4.179
r^3 = 11.395
r = 3√11.395
r = 2.25cm
To get diameter (d), we multiply the radius (r) by 2,
d = 2 × 2.25
d= 4.50cm
How is it possible for water to be polar but uncharged?
Which of the following pairs exhibit an ion-dipole interaction? a. CH_3OH and Na^+ b. Cl^- and K^+ c. CH_3CH_2CH_2CH_2CH_3 and CH_3CH_2CH_2CH_2COOH d. CH_3CH_2OH and H_2O
Answer:
a. CH_3OH and Na^+
Explanation:
Ion-dipole interaction is the forces of attraction existing between a polar compound and an ion. This particular type of ion-dipole attraction occurs between an electrostatic attraction of an ion and a dipole molecule.
From the given example, CH3OH is a polar compound, and Na^+ is an ion. Therefore, that is the only pair that exhibit the characteristics of an ion-dipole interaction.
How many different elements occur naturally?
Answer:
94 are naturally made on earth
Explanation:
Answer:
94 or 98, i think.
Explanation:
Enter a balanced equation for the reaction between aqueous lead (II) nitrite and aqueous lithium chloride to form solid lead (II) chloride and aqueous lithium nitrite.
Answer:
Pb(NO₂)₂(aq) + 2 LiCl(aq) ⇒ PbCl₂(s) + 2 LiNO₂(aq)
Explanation:
Let's consider the reaction between aqueous lead (II) nitrite and aqueous lithium chloride to form solid lead (II) chloride and aqueous lithium nitrite.
Pb(NO₂)₂(aq) + LiCl(aq) ⇒ PbCl₂(s) + LiNO₂(aq)
This is a double displacement reaction. We will start balancing Cl by multiplying LiCl by 2.
Pb(NO₂)₂(aq) + 2 LiCl(aq) ⇒ PbCl₂(s) + LiNO₂(aq)
Now, we have to balance Li by multiplying LiNO₂ by 2.
Pb(NO₂)₂(aq) + 2 LiCl(aq) ⇒ PbCl₂(s) + 2 LiNO₂(aq)
The equation is now balanced.
The balanced chemical reaction equation required is; Pb(NO2)2(aq) + 2 LiCl(aq) -----> PbCl2(s) + 2LiNO2(aq)
In order to write a balanced chemical reaction equation, we must write down the symbols of the compounds involved as follows;
lead (II) nitrite - Pb(NO2)2
lithium chloride - LiCl
lead (II) chloride - PbCl2
lithium nitrite - LiNO2
Recall that the principle of writing a balanced chemical reaction equation is that the number of atoms of each element on both sides of the reaction equation must be the same. The required balanced chemical reaction equation is;
Pb(NO2)2(aq) + 2 LiCl(aq) -----> PbCl2(s) + 2LiNO2(aq)
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Carry out the following. Please help!
A. 10^4 X 10^5
B. 10^4 X 10^-5
C. 10^4 / 10^5
Answer:
A. 10^9
B. 10^-1
C. 10^-1
I need help ASAP!! Plzz
Answer:
0.1
tenth
hundredth (0.01)
1.05 (can be anywhere from 1.00 to 1.10)
11.42 (can be anywhere from 11.40 to 11.50)
yes, it falls within reasonable doubt
Rank the following bonds in order of decreasing bond length, based on periodic trends, starting with the longest bond at the top of the list.H-S H-I H-Se H-BI. H-I II. H-SeIII. H-BrIV. H-S
Answer:
H-BI,H-Se,H-S,H-I,H-Br
Explanation:
One thing that must be kept in mind is that atomic size increases down the group and decreases across the period. The bond lengths of species are influenced by the relative sizes of atoms or ions present in the bond.
The bonds in the answer have been arranged on basis of their decreasing atomic size because the greater the atomic size of the atoms, the greater the bond length and vice versa.
Which atom is most likely to form a metallic bond?
aluminum (Al)
helium (He)
phosphorus (P)
carbon (C)
Answer:
I would say it's A just because it's make no sense for the other answers.
Aluminum atom is most likely to form a metallic bond.
METALLIC BONDS:
Metallic bonds are the kind of bonds that forms between metallic atoms. Electrons are shared between the positive ions called cations. These electrons are called localized electrons. Metallic bonds are responsible for the properties possessed by metals such as conductivity, lustre etc. Since metallic bonds forms between metal atoms, it is most likely to form between aluminum atom.Learn more: https://brainly.com/question/20511339?referrer=searchResults