Answer:
THE DISTANCE OF THE ROCK REFLECTING HER VOICE IS 82.5 METERS.
Explanation:
In sound waves, the speed of a sound is equal to twice the distance divided by time.
Mathematically,
Speed = 2 * Distance/ Time
Speed = 33- m/s
Time = 0.5 second
Distance = unknown
So re-arranging and introducing the variables into the formula, we have;
Distance = speed * time / 2
Distance = 330 * 0.5 / 2
Distance = 82.5 meters.
The distance away from the rock face which is reflecting her voice is 82.5 meters.
What is the pH of 500 mL of water after the addition of 1 mL of 2M NaOH?
Answer:
pH = 11.60
Explanation:
When we add a base, we are increasing [OH⁻], so the pH will be totally basic.
pH of water = 7
Basic pH > 7
We are adding 2 M . 1 mL = 2 mmoles
2 mmoles of OH⁻ are contained in 501 mL of total volume.
[OH⁻] = 2 mmol / 501 mL = 3.99×10⁻³ M
- log 3.99×10⁻³ M = 2.39 → pOH
pH = 14 - pOH → 11.61
Water equilibrium
2H₂O ⇄ H₃O⁺ + OH⁻ Kw = 1×10⁻¹⁴
NaOH → Na⁺ + OH⁻
1. Isotonic saline requires a concentration of 0.85% NaCl. How much solid NaCl must be weighed out on the balance to prepare a bottle full containing 3500 ml?
Given :
Concentration of NaCl , [tex]c=0.85 \%[/tex] .
To Find :
Th amount of solid NaCl must be weighed out on the balance to prepare a bottle full containing 3500 ml .
Solution :
Concentration of NaCl is 0.85 % .
It means , 0.85 gm of NaCl in 100 ml of water .
So , amount of solid NaCl required to prepare 3500 ml solution is :
[tex]x=\dfrac{3500\times 0.85}{100}\ gm\\\\x=29.75\ gm[/tex]
Therefore , amount of solid NaCl required is 29.75 gm .
Hence , this is the required solution .
The mass percentage of hydrochloric acid within a solution is 28.00%28.00% . Given that the density of this solution is 1.1411.141 g/mL, find the molarity of the solution.
Answer:
8.76M
Explanation:
Given that
Mass from the density = 1141g
According to the given situation the computation of molarity of the solution is shown below:-
we will took HCL solution which is 1000mL
HCl = 28% by mass
So,
Mass of HCl in 1-litre solution is
[tex]= \frac{28}{100} \times 1141[/tex]
Which gives the result of molar mass HCI is
= 319.48g /mol
Now,
Molarity is
[tex]= \frac{319.48}{36.45}[/tex]
Which gives results of molarity is
= 8.76M
A hybrid car holds 32 gallons of gas in its tank. If it travels from San Diego to Seattle in three tanks of gas, and gas costs $3.29 per gallon, about how much did the trip cost? Report your answer with three significant figures.
3 tanks of gas->32*3->96 gallons in total.
96*3.29->315.84
3 sig. figs. -> $315
what is the name of the salt with the structure K2S
Processes are always spontaneous when ________ ( H and S refer to the system).
Answer:
Explanation:
A spontaneous chemical process is one in which product formation is favoured under the specified conditions. A spontaneous process yields the product without an external input of energy.
A spontaneous reaction will always occur when ∆H is negative and ∆S is positive. These are the signs of enthalpy and and entropy change that gives rise to a spontaneous chemical process at all temperatures. Recall that a spontaneous process is one in which ∆G<0.
I need help with this chemistry question talking about pure substances and mixtures?
The correct answer is A. The sample is not a heterogeneous mixture
Explanation:
A heterogeneous mixture includes two or more materials and these are not completely integrated. Due to this, in most cases, if a heterogeneous mixture is filtered it is possible to separate its parts. This did not occur when Ben filtered the substance, which shows it is likely the substance is not a heterogeneous mixture. Moreover, a heterogeneous mixture does not show uniformity in terms of appearance or properties, which shows this definitely not heterogenous and Ben can safely conclude this.
How many grams are in 160 pounds?
Answer:
72574.8
Explanation:
Thats what google says
2-methyl-2-pentene Spell out the full name of the compound.
Answer:
METHYL PENTENE or 2-METHYL PENT-2-ENE
Explanation:
The number 2 carbon carries the methyl group and the double bone is on the 2 carbon as well.
The chemical structure of the compound has been attached.
I hope this is what you were looking for.
Cobalt has the chemical symbol Co and the atomic number 27. How many protons, neutrons, and electrons would be found in an atom of cobalt-58?
Answer:
COBALT
Explanation:
CO BALT COBALT
In order to calculate how many neutrons are in an atom, you must subtract the mass number from the number of protons? Neutrons = Mass # - Protons Question 6 options: True False
Answer:
True.
Explanation:
The mass number of an atom can be calculated using no of protons and the no of neutrons.
Mass number = no of protons + no of neutrons
We can rearrange the above formula to find the no of neutrons as follows :
no of neutrons = Mass number - no of protons
or
Neutrons = Mass - protons.
Hence, the given statement is true.
Formulate a hypothesis about the stoichiometry of the reaction between NaCl and AgNO3.
Answer:
AgCl + NaNO3 would be the products of the reaction between sodium chloride and silver nitrate.
The stoichiometry of this reaction is written below, and it is because for this reaction to be fulfilled the products have to be in equilibrium with the reactants, since the mass in the reaction is conserved and must be balanced in the amount of molecules that they react to each other.
Explanation:
NaCl + AgNO3 -------------- AgCl + NaNO3
which of the following tools can be used to measure mass? A.a graduated cylinder B. a triple beam balance C. a mercury thermometer D. a bathroom scale
Answer:
triple beam balance
Explanation:
The tool that can be used to measure mass is a triple beam balance. Therefore, the correct option is option B.
A graduated cylinder is used to determine a liquid's volume. A mercury thermometer is used to measure temperature. Weight is calculated on a bathroom scale and is a force rather than a mass. A typical scientific tool for calculating an object's mass is a triple beam balance.
It is composed of three beams with moveable weights that enable precise mass balancing and a pan on one end where the thing to be measured is placed. By comparing the placement of the weights on the beams to the appropriate scale, the mass of the object can be ascertained.
Therefore, the correct option is option B.
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If a dog has a mass of 21.5kg, what is his mass in the following units?
What is the dogs mass in gram?
What is the dog mass in mg?
Answer: 21.5kg in grams is 21,500 grams
21.5kg in mg is 215,000,00
Explanation:
Draw two five carbon rings that share an atom.
please help asap will give brainiest What is the independent variable in an experiment? A) The variable that remains the same throughout the experiment. B) The variable being tested in the experiment. C) The variable being measured in an experiment.
Denaturation of a protein is always permanent.
A. True
B. False
Answer:
A. True
Explanation:
This process usually cannot be reversed and will lead to the protein being permanently damaged.
The sun supplies about 1.0 kilowatt of energy for each square meter of surface area (1.0 kW/m^2 where a watt = 1 kJ/s) Plants produce the equivalent of about 0.20g of sucrose (C_12H_22O_11) per hour per square meter. Assuming that the sucrose is produced as follows, calculate the percentage of sunlight used to produce sucrose12CO2 (g) + 11H2O (I) --> C12H22O11 + 12O2(g) deltaH = 5645 kJ
Answer:
0.092 %
Explanation:
The equation of the reaction can be computed as :
[tex]12CO_2_{(g)} + 11H_2O_{(l)} \to C_{12}H_{22}O_{11} + 12O_{2_(g)}[/tex]
[tex]\Delta H = 5645 \ kJ[/tex]
recall that; the number of moles = [tex]\dfrac{mass}{molar \ mass}[/tex]
By applying the method of enthalpy of combustion for sucrose at the same time changing the time from hours to seconds, we can determine the total energy output.
i.e
[tex]=\dfrac{0.20g \ of \ sucrose }{m^2 \ 3600 \ s}\times \dfrac{1 \ mol}{342.34 \ g}\times 5.645 kJ/mol[/tex]
[tex]= 9.16 \times 10^{-4} \ kJ/m^2 s[/tex]
Given that the sun supplies about 1.0 kilowatt, to KJ/m² s, we have:
[tex]1.0 \dfrac{kW}{m^2 }= 1.0 \dfrac{kJ}{m^2 s}[/tex]
Finally, the percentage of sunlight used to produce sucrose :
= [tex]\dfrac{9.16 \times 10^{-4} \ kJ/m^2 \ s}{1.0 \ kJ/m^2 . s} \times 100\%[/tex]
= 0.092 %
what is neutralisation reaction?
Answer:
In chemistry, neutralization or neutralisation (see spelling differences) is a chemical reaction in which acid and a base react quantitatively with each other. In a reaction in water, neutralization results in there being no excess of hydrogen or hydroxide ions present in the solution.
Answer:
A neutralization reaction is when an acid and a base react to form water and a salt and involves the combination of H+ ions and OH- ions to generate water. The neutralization of a strong acid and strong base has a pH equal to 7
Explanation:
why is the pull of gravity more at the poles than at than at the equator.
Answer:
Why the gravitational force is greater near the poles and less at equator?
Gravitational force of Earth is minimum at equator because the centrifugal force at the equator is maximum.
Centrifugal force is an outward force exerted on a body revolving in a circular path, to mantain its state of motion.
Explanation:
Here Earth revolves around its axis and the same forces act on it to enable its revolution.
Gravitational force at the equator is less because Centrifugal force, which is also acting at the equator cancels out the Gravitational force to an extent. Whereas at poles, there is no such effect of centrifugal force because earth is sphere (bulged at center; flat at poles )and hence gravitational force is maximum at poles.
The other reason is distance from any place on equator to centre of earth is more than at poles. Because Earth is bulged at centre and flat at poles. Since Gravitational force is given by
F= GMm/ r^2 ; r is the distance between two bodies.
What is the relationship between grams and cm³?
Answer:
1 gram
Explanation:
1 gram= weight of 1 cubic centimeter of pure water at temperature 4°C = 1000 milligrams = 0.001 kilogram
Characteristics of this mineral: sheet-silicate mineral with one dominant direction of cleavage (breaks into flakes and sheets), thin sheets are silvery gray and partially transparent, does not effervesce.
Answer: The mineral you are describing is Muscovite Mica
I hope that this helps you !
The Characteristics of the mineral should be Muscovite
What is Muscovite?It is also known as the common mica, etc. It comprises of potassium & almunium. It should be the most common member of the mica group. It is considered as the mineral that contains one dominant direction of cleavage split into the flake & sheets, Also, due to the perfect cleavage, it can arise in thin, transparent, and the durable sheet.
Therefore, The Characteristics of the mineral should be Muscovite
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4. In a chemical process, you need to force a compound to bond with a halogen, causing it to lose hydrogen. Which type of reaction do
you need to perform?
A. Halogenation
B. Hydrolysis
C. Reduction
D. Ammoniation
Answer:
Halogenation
Explanation:
Halogenation is a type of substitution reaction in which a hydrogen atom is replaced by a halogen atom in a molecule.
The molecule looses its hydrogen atom as the halogen is introduced into the molecule. This sort of reaction is very common in organic chemistry. Many hydrocarbons can be halogenated in the presence of light.
Pick the compound with the highest boiling point in each pair. Match the words in the left column to the appropriate blanks in the sentences on the right. Make certain each sentence is complete before submitting your answer.1. For the pair of compounds CO2 or NO2 the one with the highest boiling point is __________ . 2. For the pair of compounds NH3 or CH4 the one with the highest boiling point is _________ 3. For the pair of compounds CS2 or CO2 the one with the highest boiling point is _________
Answer:
1) NO2
2) NH3
3) CS2
Explanation:
CO2 is a nonpolar molecule owing to the fact that the two opposing dipoles in the molecule cancels out. Hence its primary intermolecular forces are the weak dispersion forces. How ever NO2 is polar and its molecules are held together by dipole-dipole interaction this makes the boiling point of NO2 greater than that of CO2
NH3 exhibits hydrogen bonding since nitrogen is far more electronegative than hydrogen. However, CH4 is nonpolar and the only intermolecular forces present are weak dispersion forces. This accounts for the fact that NH3 has a greater boiling point than CH4.
The boiling point of a compound also depends on its molecular mass. CS2 has a greater boiling point than CO2 due to the fact that CS2 has a larger molecular mass. The both compounds- CO2 and CS2 has exactly the same kind of intermolecular forces present between their molecules- the weak dispersion forces.
when are larger atoms least likely to be reactive
Answer:
when they have eight valence electrons.
Explanation:
When atoms do not have a full valence shell, the atoms are more likely to react with other and vice versa.
Answer:
When they have a full shell of electrons
Explanation:
and or eight valence electrons
What are ions exactly?
Are atoms with an incomplete outer valence shell called ions?
Answer:
An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. ... When an atom is attracted to another atom because it has an unequal number of electrons and protons, the atom is called an ION.
Explanation:
There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. In the first step, calcium carbide and water react to form acetylene and calcium hydroxide:
CaC2(s) + 2H2O(l) → C2H2(g) + Ca(OH)2(s)ΔH = −414kJ
In the second step, acetylene, carbon dioxide and water react to form acrylic acid:
6C2H2(g) + 3CO2(g) + 4H2O(g) → 5CH2CHCO2H(g)ΔH = 132kJ
Calculate the net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water, and carbon dioxide from these reactions. Round your answer to the nearest kJ.
Answer:
ΔH = -470.4kJ
Explanation:
It is possible to sum 2 or more reactions to obtain the ΔH of the reaction you want to study (Hess's law). Using the reactions:
1. CaC2(s) + 2H2O(l) → C2H2(g) + Ca(OH)2(s)ΔH = −414kJ
2. 6C2H2(g) + 3CO2(g) + 4H2O(g) → 5CH2CHCO2H(g)ΔH = 132kJ
6 times the reaction 1.
6CaC2(s) + 12H2O(l) → 6C2H2(g) + 6Ca(OH)2(s)ΔH = −414kJ*6 = -2484kJ
This reaction + 2:
6CaC2(s) + 3CO2(g) + 16H2O(l) → + 6Ca(OH)2(s) + 5CH2CHCO2H(g) ΔH = -2484kJ + 132kJ = -2352kJ
As we want to calculate the net change enthalpy in the formation of just 1 mole of acrylic acid we need to divide this last reaction in 5:
6/5CaC2(s) + 3/5CO2(g) + 16/5H2O(l) → + 6/5Ca(OH)2(s) + CH2CHCO2H(g) ΔH = -2352kJ / 5
ΔH = -470.4kJIndicate the direction of polarity of each of the covalent bonds by placing the appropriate delta notation next to each end of the bond. C-O, O-CL, O-F, C-N, C-L, S-H, S-CL
Answer:
C→O, O→Cl, O→F, C→N, C←Li, S ←H, S→Cl
Explanation:
The general convention for indicating polarity in molecules is that of showing the direction of polarity from the positive to the negative part of the bond. This is indicated in the answer by arrows that show the direction of the dipole.
The negative end of the dipole must be the more electronegative element while the positive end of the dipole is the less electronegative element, hence the answer shown above.
The delta notation, indicating the polarity of for the presented covalent bonds are:
δ+ C-O δ-δ- O-Cl δ+δ+ O-F δ-δ+ C-N δ-δ+ C-Cl δ-δ- S-H δ+δ+ S-Cl δ-Polar bonds are those in which atoms have different electronegativities.
The delta notation is used to indicate the direction of the polarity.
The atom with the greater electronegativity acquires a partial negative charge (goes with the symbol δ-), while the atom with the lesser electronegativity acquires a partial positive charge (goes with the symbol δ+).
Let's consider the following elements with their electronegativities.
C (2.5)O (3.5)Cl (3.0)F (4.0)N (3.0)S (2.5)H (2.1)The delta notation for the presented bonds are:
δ+ C-O δ-δ- O-Cl δ+δ+ O-F δ-δ+ C-N δ-δ+ C-Cl δ-δ- S-H δ+δ+ S-Cl δ-Learn more: https://brainly.com/question/2734316
Which of the following is a valid conversion factor:
10m/1dm
1mL/100L
100cg/1g
1cm^3/1L
If a 250mL beaker weighs 13.473g and the same beaker plus 2.2 mL of water weighs 15.346g. How much does the 2.2 mL of water, alone, weigh? Show your work for the calculation. Be sure to use significant figures.
Given :
A 250 ml beaker weighs 13.473 g .
The same beaker plus 2.2 ml of water weighs 15.346 g.
To Find :
How much does the 2.2 ml of water, alone, weigh .
Solution :
Now, mass of water is given by :
[tex]\text{Mass of water alone = Total mass - Mass of beaker alone}\\\\Mass =15.346-13.473\ g\\\\Mass =1.873\ g[/tex]
Therefore , mass of 2.2 ml of water alone is 1.873 g .
Hence , this is the required solution .