Answer: The Equator because it divides the Earth into the Northern and Southern hemispheres.
Explanation:
Explain how a cold compress used by
athletes is an endothermic or exothermic
reaction.
Please helppp
Answer: A cold compress used by athletes is an endothermic reaction.
Explanation:
A pack of cold compress used by athletes contains water that holds another bag or tube inside it which is filled with ammonium nitrate fertilizer.
So, on hitting the cold compress the tube breaks down due to which fertilizer gets mixed with water. This mixture absorbs the heat when placed on the area of body having pain, strain or bump.
As a result, we tend to feel cold at the affected area of our body.
Thus, we can conclude that a cold compress used by athletes is an endothermic reaction.
List all the metals in the alkaline earth metals group
Answer:
beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
Alkaline earth metals are those that have two valence electrons in their outermost shell.
Barium (Ba), Radium (Ra), Strontium (Sr), Magnesium (Mg), Calcium (Ca), and Beryllium (Be) are the six alkaline earth metals.
By donating their outermost electrons, they take on the noble gas electron configuration, which increases their stability. When electrons are transferred to an atom with an electronegative charge, the alkaline earth metals get a positive charge.
The second column of the periodic table contains alkaline earth metals, which are very reactive metals. These metals are the building blocks of the entire world. These metals are typically found as sulfates in nature.
A few examples of minerals are gypsum, calcium sulfate, epsomite, magnesium sulfate, barite, and barium sulfate.
to learn more about "Alkaline earth metals" here:
brainly.com/question/27786158
What volume of solution must be added to 4.0 mol of NaCl to make a 1.2 M solution?
Answer:
[tex]\boxed {\boxed {\sf 3.3 \ liters}}}[/tex]
Explanation:
Molarity is a measure of concentration in moles per liter.
[tex]molarity=\frac{moles \ of \ solute}{liters \ of \ solution}}[/tex]
The solution has a molarity of 1.2 M or 1.2 moles per liter. There are 4.0 moles of NaCl, the solute. We don't know the liters of solution, so we can use x.
molarity= 1.2 mol/L moles of solute= 4.0 mol liters of solution =xSubstitute the values into the formula.
[tex]1.2 \ mol/L = \frac{4.0 \ mol}{x}[/tex]
Since we are solving for x, we must isolate the variable. Begin by cross multiply (multiply the 1st numerator and 2nd denominator, then the 1st denominator and 2nd numerator.
[tex]\frac {1.2 \ mol/L}{1}=\frac{ 4.0 \ mol}{x}[/tex]
[tex]4.0 \ mol *1=1.2 \ mol/L *x[/tex]
[tex]4.0 \ mol = 1.2 \ mol/L *x[/tex]
x is being multiplied by 1.2 moles per liter. The inverse of multiplication is division, so divide both sides by 1.2 mol/L
[tex]\frac{4.0 \ mol}{1.2 \ mol/L} = \frac{1.2 \ mol/L *x}{1.2 \ mol/L}[/tex]
[tex]\frac{4.0 \ mol}{1.2 \ mol/L}=x[/tex]
The units of moles (mol) will cancel.
[tex]\frac{4.0 }{1.2 } \ L =x[/tex]
[tex]3.33333333 \ L=x[/tex]
The original measurements both have 2 significant figures, so our answer must have the same. For the number we found, this is the tenths place.
The 3 in the hundredth place tells us to leave the 3 in the tenths place.
[tex]3.3 \ L\approx x[/tex]
Approximately 3.3 liters of solution are needed to make a 1.2 M solution with 4.0 moles of sodium chloride.
Draw the Lewis structure (including resonance structures) for methyl azide (CH3N3). For each resonance structure, assign formal charges to all atoms that have formal charge. Draw the Lewis structure (including resonance structures) for methyl azide (CH3N3). For each resonance structure, assign formal charges to all atoms that have formal charge.
Answer:
N atom ( bounded to two Nitrogen atoms ) has a + formal charge while the N atom bounded to only one (1) Nitrogen atom has a - formal charge .
Explanation:
Diagram Lewis structure of methyl azide ( attached below )
Generally CH3N3 has two(2) resonance structures
What is found in both structures is that the N atom ( bounded to two Nitrogen atoms ) has a + formal charge while the N atom bounded to only one (1) Nitrogen atom has a - formal charge .
Attached below are the two resonance structures
All solutions must be a liquid-liquid combination.
True
False
student titrated 15.00 mL of HCl of an unknown concentration with a solution of 0.0670 M NaOH. This titration used 19.06 mL of the 0.0670 M NaOH to reach the end point. Determine the concentration of the unknown HCl in one set up. You may look at the steps used in the previous problem to recall what fractions need to be in the set-up to solve this problem. 1. Fill in the fractions required to determine the concentration of HCl.
Answer:
The concentration of the unknown HCl is 0.0851 M.
Explanation:
The equation of neutralization:
[tex]n_1M_1V_1=n_2M_2V_2[/tex]
Where:
[tex]n_1[/tex]= Basicity of acid
[tex]n_2[/tex] = Acidity of base
[tex]M_1[/tex]= concentration of acid
[tex]M_2[/tex]= concentration of base
[tex]V_1[/tex] = Volume of acid used in neutralization
[tex]V_2[/tex] = Volume of base used in neutralization
We have:
The acidity of HCl = [tex]n_1=1[/tex]
The concentration of HCl solution used = [tex]M_1=?[/tex]
The volume of HCl used in titration =[tex]V_1= 15.00 mL[/tex]
The acidity of NaOH =[tex]n_2=1[/tex]
The concentration of NaOH solution used = [tex]M_2=0.0670 M[/tex]
The volume of NaOH used in titration =[tex]V_2= 19.06 mL[/tex]
[tex]n_1M_1V_1=n_2M_2V_2\\1\times M_1\times 15.00 mL=1\times 0.0670 M\times 19.06 mL\\M_1=\frac{1\times 0.0670 M\times 19.06 mL}{1\tines 15.00 mL}\\M_1=0.085135 M\approx 0.0851 M[/tex]
The concentration of the unknown HCl is 0.0851 M.
1 atm = 760 torr
For isooctane:
For tetramethylbutane:
There is no other feasible arrangement of “tetramethylbutane” it is redundant in this circumstance.
What is Tetramethylbutane?Tetramethylbutane, often known as hexamethylethane, is a hydrocarbon with the chemical formula C8H18 or (H3C-)3C-C(-CH3)3. It is the most branching and compact of the several octane isomers, as well as the only one having a butane (C4) backbone.
It has a highly symmetrical structure, a high melting point, and a narrow liquid range; in fact, it is the smallest saturated acyclic hydrocarbon that emerges as a solid at 25 °C. (Cubane, C8H8, is much smaller and solid at room temperature among cyclic hydrocarbons.) It is also the most stable C8H18 isomer, with a lower heat of formation of 4.18 kcal/mol (17.5 kJ/mol) than n-octane, which has been related to dispersive interactions (electron correlation) between the methyl groups (protobranching).
To learn more about Tetramethylbutane to refer:
https://brainly.com/question/28601156
#SPJ1
How many moles of C6H12O6 are needed to produce 38.44 grams of CO2? Round your answer to three digits after the decimal point.
C6H12O6 + 6 O2 à 6 CO2 + 6 H2O
Explanation:
38.44 g CO2 = 0.873 mol CO2
0.873 mol CO2 × (1 mol C6H12O6 / 6 mol CO2)
= 0.146 mol C6H12O6 x (180.56 g C6H12O6/ 1 mol C6H12O6)
= 26.303 gm
Please i need help with this it is Which of the following is not a property of matter that you could use to distinguish one substance from another.
Answer:
I believe it's mass? I may be wrong though...
the volume of the balloon was 4.21L when the temperature was 25.0°C, what will the volume of the balloon be when the temperature is 50.0°C?
If the volume of the balloon was 4.21L when the temperature was 25.0°C, 8.42L will be the volume of the balloon be when the temperature is 50.0°C. if Mass and pressure is constant.
What is the relation between Volume and temperature?The volume of a fixed mass of gas is linearly proportional to temperature at given constant pressure. In simple words the volume of a fixed mass of a gas reduces when it is cooled and increases when the temperature is raised.Hence, in the above case it is shown that temperature is rising twice of its original value so, the volume of that given mass of gas in the balloon will also increase by twice.
Solution:
4.21L=25.0°C
4.21L×2=50.0°C
8.42L=50.0°C
8.42L will be the volume of the balloon be when the temperature is 50.0°C.
To know more about volume visit
https://brainly.com/question/12050285
#SPJ1
sap can be turned into syrup by
Answer: by boiling it
Explanation:
By boiling the sap to remove water, also to concentrate the sugar that makes maple syrup.
Small amount of acid is added to Water during electrolysis of water . Why?
Answer:
Water doesn't have ions that are needed to pass the electricity so in order to increase the no of ions we poor acid into the water. Just increasing the no ions will increase the electricity flow faster
Nitrogen monoxide and oxygen can be formed from the thermal decomposition of nitrogen dioxide.
2NO2 (g) = 2NO (g) + O₂(g)
In an experiment, 4 moles of nitrogen dioxide were put into a 1.0 dm³ container and heated
to a constant temperature. The equilibrium mixture contains 0.8 moles of oxygen.
What is the value of the equilibrium constant, Kc?
1.5 POINTS
A
C
E
LU
0.032
0.853
0.426
B
D
0.222
0.356
FINISH QUIZ
Answer:
0.355 moldm^-3
Explanation:
Which of the following relations are functions?
For the reaction C + 2H2 → CH4, how many grams of carbon are required to produce 14 moles of methane, CH4 ?
Round your answer to the nearest tenth. If you answer is a whole number like 4, report the answer as 4.0
Use the following molar masses. If you do not use these masses, the computer will mark your answer incorrect.:
Element Molar Mass
Hydrogen 1
Carbon 12
The amount, in grams, of carbon required to produce 14 moles of methane according to the reaction would be 168.0 grams.
Stoichiometric problemFrom the balanced equation of the reaction, the mole ratio of the carbon that reacts and the methane produced is 1:1. In other words, 1 mole of carbon will produce 1 mole of methane.
Thus, for the production of 14 moles of methane:
1 mole methane = 1 mole carbon
14 moles methane = 14 x 1/1 = 14 moles carbon.
Recall that, mass = mole x molar mass.
The molar weight of carbon is given as 12 g/mol
Mass of 14 moles carbon = 14 x 12 = 168 grams
In other words, for the illustrated reaction, the amount of carbon required to produce 14 moles of methane would be 168.0 grams.
More on stoichiometric problems can be found here: https://brainly.com/question/29775083
#SPJ1
You can change a subscript in an equation, but you cannot change the
coefficient.
O True
O False
Answer:
false
because you can't change a subscript ,
but you can change the coefficient.
Carbon disulfide is a colorless, volatile, highly flammable liquid with a very unpleasant smell that is used as a solvent in some laboratory applications.
a. True
b. False
An object has a mass of 0.0124 kg and a volume of 1893 mm^3. What is its density in grams per cubic centimeter?
Answer:
[tex]d=6.34g/cm^3[/tex]
Explanation:
Hello there!
In this case, since the calculation of density is performed by dividing the mass over volume:
[tex]d=\frac{m}{V}[/tex]
Which gives us a better understanding of the degree of compactness of the object; we can find the required density in grams per cubic centimeter by applying the following dimensional analysis in the aforementioned equation:
[tex]d=\frac{0.0124kg}{1893mm^3} *(\frac{10mm}{1cm} )^3*\frac{1000g}{1kg}\\\\d=6.34g/cm^3[/tex]
Regards!
What can be added to a solution to control the pH?
a base
a liquid
a buffer
an acid
Answer:
liquid
Explanation:
Adjusting pH in Water
Pure or distilled water has a pH level of 7, which means it is neutral. If you want to increase the pH of water, you must add an alkaline substance, such as baking powder, to it. If you want to decrease the pH of water, you add an acidic substance, such as lemon juice, to it
A buffer can be added to a solution to control the pH. The correct option is c.
What is pH?PH is potential hydrogen. It is the value of how acidic or alkaline, the solution is.
The pH scale is consisting of 1 to 14 measure numbers, a pH less than 7 is acidic and a pH more than 7 is basic.
A buffer is a solution that maintains the pH of any solution.
Thus, the correct option is C, a buffer.
Learn more about pH
https://brainly.com/question/491373
Form a group and discuss the possible reasons why EA, is a positive quantity for oxygen atom.
Answer:
Possible reasons why EA, or electronegativity, is a positive quantity for oxygen atom include:
Explanation:
When a person weighs himself in pounds, which system of measurement is he using?
Answers: customary or metric
Answer:
it is the British imperial and united states customary systems
What is also known as neutralization? 1. Acid-base 2. Redox 3. Precipitation
Answer:
acid base
Explanation:
plz mark me brainliest
When the conductivity is at a minimum, what must be true about the amount of Ba(OH)2?
When the conductivity is at a minimum, the true thing about the amount of Ba(OH)₂ is that the amount of the two reactants are the same when conductivity is low.
What is conductivity?The ability of an aqueous solution to carry an electric current is measured by its conductivity. Ionic strength is measured by conductivity monitors. In automated chromatography systems, conductivity is the main input control parameter used to enable the generation of salt gradients or to control buffer dilution or in-line buffer preparation.
Conductivity monitors can be used to automate and monitor cleaning and equilibration procedures. It's important to remember that temperature affects measurements of conductivity and pH.
When conductivity is low, the amounts of the two reactants are equal. Between the reactants, there are no excesses. The aqueous solution cannot dissolve the precipitate BaSO₄. Since there are no ions, the conductivity is at its lowest.
Learn more about conductivity on:
https://brainly.com/question/1851658
#SPJ1
Complete question
The Ba(OH)₂ dissociates as Ba+2 + 2 OH-. H₂SO₄ dissociates as 2 H+ + SO₄-2. When the conductivity is at a minimum, what must be true about the amount of Ba(OH)₂ compared to H₂SO₄
Use the data in the table below to calculate the heat of vaporization (AHvap) in kJ/mol of pinene.
Vapor Pressure
(torr)
760
515
340
218
135
Temperature
(K)
429
415
401
387
373
kJ/mol
Use the value of AHyap determined in Part 1 to calculate the vapor pressure of pinene (in torr) at room temperature (23°C)
760
torr
Answer:
41 kJ/mol4 torrExplanation:
Given pinene has a (temperature, vapor pressure) relation (K, torr) = {(373, 135), (429, 760)}, you want the heat of vaporization in kJ/mol and the vapor pressure at room temperature (23 °C).
Clausius–Clapeyron EquationThe Clausius–Clapeyron equation can be used to find the heat of vaporization:
[tex]\ln{P}=-\dfrac{\Delta H_{\text{vap}}}{R}\left(\dfrac{1}{T}\right)+C[/tex]
Solving for ∆H, we find ...
[tex]\Delta H_{\text{vap}}=-\dfrac{R\cdot\ln{\dfrac{P_1}{P_2}}}{\dfrac{1}{T_1}-\dfrac{1}{T_2}}\\\\\\\Delta H_{\text{vap}}=-\dfrac{8.314\cdot\ln{\dfrac{760}{135}}}{\dfrac{1}{429}-\dfrac{1}{373}}\approx 41052.8[/tex]
The heat of vaporization of pinene is about 41 kJ/mol.
Vapor pressureRearranging the above equation to give P1, we have ...
[tex]\ln{\dfrac{P_1}{P_2}}=-\dfrac{\Delta H_\text{vap}}{R}\left(\dfrac{1}{T_1}-\dfrac{1}{T_2}\right) \\\\\\P_1=P_2\cdot e^{-\frac{\Delta H_\text{vap}}{R}\left(T_1^{-1}-T_2^{-1})}[/tex]
Using the same P2 and T2 as above, we find the vapor pressure at room temperature (296.15 K) to be ...
P1 ≈ 4.349 . . . . . torr
The vapor pressure of pinene at room temperature is about 4 torr.
how many grams of KOH do we need to make 250.0ml of a 0.75 M
Answer:
10.52g KOH
Explanation:
250.0 ml X 1L/1000ml X 0.75 mol KOH/1L X 56.105gKOH/1 mol KOH =10.52g KOH
A gas occupies 400.0 mL at 20.00 C and 70.00 kPa. What will the pressure be at 40.00 C and 200.0 mL ?
Answer: The new pressure is 280 kPa.
Explanation:
Given: [tex]V_{1}[/tex] = 400.0 mL, [tex]T_{1} = 20^{o}C[/tex] , [tex]P_{1}[/tex] = 70.0 kPa
[tex]V_{2}[/tex] = 200.0 mL, [tex]T_{2} = 40.0^{o}C[/tex], [tex]P_{2}[/tex] = ?
Now, combined gas law is used to calculate the new pressure as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}[/tex]
Substitute the values into above formula as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{70.0 kPa \times 400.0 mL}{20^{o}C} = \frac{P_{2} \times 200.0 mL}{40.0^{o}C}\\P_{2} = 280 kPa[/tex]
Thus, we can conclude that the new pressure is 280 kPa.
What is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers?
Answer:
the correct answer is 6...
Answer:
The answer is 2
please help me! ASAP
Answer:
(1) 4- ethyl -6 methyl -2 octyne
Which of these is an example of a physical property?
A. Iron combines with oxygen to rust.
B. Potassium reacts in water to form a base.
C. Sodium metal is soft and malleable.
D. Sodium ignites when placed in water.
Option C. Sodium metal is soft and malleable is an example of a physical property.
What is a physical property?A physical property can be defined as any feature of a substance that can be really observed and also measured without changing its chemical composition such as for example, the color, density of a metal, boiling point, conductivity, etc.
Therefore, with this data, we can see that physical properties have a significant impact on the performance and use of a given chemical product and they are associated with intrinsic features of the chemical material that forms molecules.
Learn more about physical properties here:
https://brainly.com/question/12330204
#SPJ1
Without doing a calculation, arrange the following group of molecules in order of decreasing standard molar entropy (S^o ):
hexane (C6H14), benzene (C6H6), cyclohexane (C6H12)
a. C6H14 > C6H6 > C6H12
b. C6H6 > C6H12 > C6H14
c. C6H12 > C6H14 > C6H6
d. C6H14 > C6H12 > C6H6
e. C6H12 > C6H6 > C6H14
f. C6H6 > C6H14 > C6H12
Answer:
d. C6H14 > C6H12 > C6H6
Explanation:
Standard molar entropy has to do with the number of atoms that are present in each of the species. The greater the number of atoms possessed by the species, the higher the value of the standard molar entropy due to a greater number of vibration modes.
Hexane (C6H14) has the highest number of atoms followed by cyclohexane (C6H12) and lastly benzene (C6H6).
Thus the order of decreasing molar entropy is; C6H14 > C6H12 > C6H6.