Answer:
as it has 17000 joules and 1 calorie has 4184 joules, this yogurt serving has 4.06 calories
Why do field researchers work with tribal healers in their search for new rainforest drugs
Answer:
See explanation
Explanation:
Drugs are obtained from plants. The rainforest zone has abundance of a variety of plant species due to the plentitude of rainfall all year round.
Many of these plants have known medicinal properties and have been used by tribal healers to cure diverse ailments.
Field researchers need to work closely with these tribal healers to identify plant species with observed medicinal properties. These plant species are now studied scientifically and the active ingredients in them are extracted and used to produce new potent drugs.
A diver exhales a bubble with volume of 250 mL at pressure of 2.4 atm and temperature of 15 C. How many gas particulate in this bubble?
Answer:
1.5x10²² particulates
Explanation:
Assuming ideal behaviour, we can solve this problem by using the PV=nRT formula, where:
P = 2.4 atmV = 250 mL ⇒ 250 / 1000 = 0.250 Ln = ?R = 0.082 atm·L·mol⁻¹·K⁻¹T = 15 °C ⇒ 15 + 273 = 288 KWe input the given data:
2.4 atm * 0.250 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 288 KAnd solve for n:
n = 0.025 molFinally we calculate how many particulates are there in 0.025 moles, using Avogadro's number:
0.025 mol * 6.023x10²³ particulates/mol = 1.5x10²² particulatesWhat is erosion?
A) Weathered materials staying in one place
B) The movement of weathered materials by wind, water or ice
C) New materials on a land form
Answer:
B. The movement of weathered materials by wind, water or ice.
A buffer solution contains 0.368 M hydrocyanic acid and 0.360 M potassium cyanide . If 0.0513 moles of sodium hydroxide are added to 225 mL of this buffer, what is the pH of the resulting solution
Solution :
Millimoles of hydrocyanic acid = 225 x 0.368
= 82.8
Millimoles of potassium cyanide = 225 x 0.360
= 81
Millimoles of sodium hydroxide = 51.3
Therefore,
pOH = pKb + log [salt - C / bas + C]
= 4.74 + log[82.8 - 51.3 / 81 + 51.3]
= 4.102
Therefore, pH = 9.05
Gaseous methane CH4 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 0.963 g of methane is mixed with 1.2 g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to 2 significant digits.
Answer:
[tex]m_{H_2O}=0.676gH_2O[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to calculate the maximum mass of water by firstly setting up the undergoing chemical reaction as follows:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
Thus, we are able to firstly calculate the moles of water produced by both methane and oxygen in order to identify the limiting reactant, which is related to maximum of water:
[tex]0.963 gCH_4*\frac{1molCH_4}{16gCH_4}*\frac{2molH_2O}{1molCH_4} =0.120molH_2O\\\\1.2gO_2*\frac{1molO_2}{32gO_2}*\frac{2molH_2O}{2molO_2} =0.0375molH_2O[/tex]
Thus, we infer the limiting reactant is O2 and therefore we can obtain up to 0.0375 moles of water, which are related to the following mass:
[tex]m_{H_2O}=0.0375molH_2O\frac{18.02gH_2O}{1molH_2O}=0.676gH_2O[/tex]
Regards!
An infant acetaminophen suspension contains 80 mg/0.80 mL suspension. The recommended dose is 15 mg/kg body weight.
How many milliliters of this suspension should be given to an infant weighing 13 lb.
Answer:
0.8853 mL
Explanation:
First we convert 13 lb to kg, keeping in mind that 1 lb = 0.454 kg:
13 lb * [tex]\frac{0.454kg}{1lb}[/tex] = 5.902 kgThen we calculate how many mg of acetaminophen should be given, using the recommended dose and infant mass:
15 mg/kg * 5.902 kg = 88.53 mgFinally we calculate the required mL of suspension, using its concentration:
88.53 mg ÷ (80 mg/0.80 mL) = 0.8853 mLWhat is the total number of joules released when a 5.00-gram sample of water changes from liquid to solid a 0° C?
what is the pH value of water
Answer:
The pH of pure water (H20) is 7 at 25oC, but when exposed to the carbon dioxide in the atmosphere this equilibrium results in a pH of approximately 5.2. Because of the association of pH with atmospheric gasses and temperature, it is strongly recommended that the water be tested as soon as possible.
Molecule contains carbon, hydrogen and sulfur atoms. When a sample of 0.535g of this compound is burnt in oxygen, 1.119 g of CO2and 0.229 gof H2O and 0.407g of SO2are obtained.
Calculate its empirical formula.
Answer:
The empirical formula is, C4H4S
Explanation:
Number of moles of carbon = 1.119 g/ 44g/mol = 0.025 moles
Mass of Carbon= 0.025 moles × 12 g/ mole = 0.3 g
Number of moles of hydrogen = 0.229/18g/mol × 2 = 0.025 moles
Mass of hydrogen = 0.025 moles × 1 = 0.025 g
Number of moles of sulphur = 0.407g/ 64 g/mol = 0.0064 moles
Mass of sulphur= 0.0064 moles ×32 = 0.2 g
Now we obtain the mole ratios by dividing through by the lowest ratio.
C- 0.025 moles/ 0.0064 moles, H- 0.025 moles/ 0.0064 moles, S- 0.0064 moles/0.0064 moles
C4H4S
Calculate the molality of a 35.4 % (by mass) aqueous solution of phosphoric acid (H3PO4) (35.4 % means 35.4 g of H3PO4in 100 g of solution)
Answer:
3.6124 m/kg
Explanation:
Molality is calculated as moles of solute (mol) divided by kilogram of solvent (kg). Here, we can find these numbers by using the 35.4%, which gives us 35.4 g of H3PO4 and 100 g of solution to work with.
To go from grams to moles for the phosphoric acid, you need to find the molar mass of the compound or element and divide the grams of the compound or element by that molar mass.
Here, the molar mass for phosphoric acid is 97.9952 g/mol. The equation would look like this:
35.4 g x 1 mol / 97.9952 g = 0.3612422 mol
Next, the 100 g of solvent can easily be converted to 0.1 kg of solvent.
To find the molality, divide the moles of solute and kilograms of solution.
0.3612422 mol / 0.1 kg = 3.6124 m/kg
Identify the alkene obtained on dehydration of each of the following alcohols:
a. 3-Ethyl-3-pentanol
b. 1-Propanol
c. 2-Propanol
d. 2,3,3-Trimethyl-2-butanol
Answer:
Explanation:
The information below explains how dehydration of alcohol occurs to produce alkene.
Under the influence of a catalyst, alcohol dehydrates to produce an alkene and water. To produce alkene and water, the reaction eliminates the OH group from alcohol containing the carbon atom and the hydrogen atom from a neighboring carbon atom via the same molecule.
The –OH group in alcohol contribute two(2) electrons to H+ out from the acid reagent, resulting in the formation of an alkyloxonium ion. This ion serves as an excellent leaving group, allowing a carbocation to form. The nucleophile which acts as the deprotonated acid subsequently attacks and creates a double bond with the hydrogen next to the carbocation.
What is the molar mass of Na2SO4?
O A. 142.04 g/mol
O B. 71.05 g/mol
O c. 238.22 g/mol
O D. 94.04 g/mol
Answer: A. 142.04 g/mol
Explanation:
A particular Ci atom has a mass number of 37. Which statements about the atom are correct?
Check all that apply.
It contains 37 protons.
It contains 20 neutrons.
It has an atomic number of 17.
It contains 37 neutrons.
Answer:
It contains 20 neutrons
It has an atomic number of 17.
Explanation:
According to this question involving chlorine atom (Cl), the mass number (A) is said to be 37. The mass number of an element is calculated by adding the proton number and the neutron number i.e.
Mass no. = Proton no. + Neutron no.
The proton number is also called atomic number, and in this case as it is on the periodic table, the atomic number of Chlorine is 17. This means that chlorine atom has 17 protons. To calculate the number of neutrons in 37Cl, we say:
neutron no. = 37 - 17
neutron no = 20
From the above calculation, the following are true of 37 Cl:
- It contains 20 neutrons
- It has an atomic number of 17.
The chlorine atom contains 20 neutrons .
It has an atomic number of 17.
Explanation:
The atomic number of an atom is equal to the number of protons in an atom.The mass number of the atom is equal to the sum of the number of protons and the number of neutrons.Given:
The mass number of a given chlorine atom is 37.
To find:
The correct statements.
Solution:
The atomic number of chlorine is 17
The number of protons in chlorine atom = atomic number of chlorine = 17
Mass number = Number of protons + Number of neutrons
37 = 17+ Number of neutrons
Number of neutrons = 37 - 17 = 20
The chlorine atom contains 20 neutrons and has an atomic number of 17.
So, the correct statements are 'the chlorine atom contains 20 neutrons',
'It has an atomic number of 17'.
Learn more about subatomic particles here:
brainly.com/question/1371394?referrer=searchResults
brainly.com/question/2099804?referrer=searchResults
Perform the calculations and determine the absolute and percent relative uncertainty. Express each answer with the correct number of significant figures.
a. [9.8(±0.3)−2.31(±0.01)]8.5(±0.6)= __________
b. absolute uncertainty: __________
c. absolute uncertainty: _________
d. percent relative uncertainty: ___________
Answer:
Explanation:
Given the equation:
[tex]\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}[/tex]
The absolute uncertainty in a measurement is the term used to describe the degree of inaccuracy.
The first step is to determine the algebraic value on the numerator.
Algebraic value = 9.8 - 231
= 7.49
The absolute uncertainty = [tex]\sqrt{(abs. uncertainty_{v_1})^2+(abs. uncertainty_{v_2})^2}[/tex]
absolute uncertainty = [tex]\sqrt{(0.3)^3 + (0.01)^2}[/tex]
= [tex]\sqrt{0.09 + 0.0001}[/tex]
= 0.300167
∴
[9.8(±0.3) - 2.31(±0.01)] = 7.49(±0.300167)
The division process now is:
[tex]\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}= \dfrac{7.49 (\pm 0.300167)}{8.5 (\pm0.6)}[/tex]
Relative uncertainty = [tex]\dfrac{(\pm 0.300167)}{7.49}\times 100 \ , \ \dfrac{(\pm 0.6) }{8.5} \times 100[/tex]
Relative uncertainty = ±4.007565% , ±7.058824%
[tex]\text{Relative uncertainty} = \sqrt{(4.007565)^2+(7.058824)^2}[/tex]
[tex]\text{Relative uncertainty} = \sqrt{16.06057723+49.82699626}[/tex]
[tex]\text{Relative uncertainty} = \sqrt{65.88757349}[/tex]
[tex]\text{Relative uncertainty} = 8.117116[/tex]
≅ 8%
The algebraic value = [tex]\dfrac{7.49}{8.5}[/tex]
= 0.881176
≅ 0.88
The percentage of the relative uncertainty =[tex]\dfrac{\text{Absolute uncertainty }}{\text{calculated value} }\times 100[/tex]
By cross multiplying:
[tex]\text{Absolute uncertainty} (\%) = \dfrac{\text{relative uncertainty} \times \text{calculated value}}{100}[/tex]
[tex]\text{Absolute uncertainty} (\%) = \dfrac{8.117116\times 0.881176}{100}[/tex]
[tex]\text{Absolute uncertainty} (\%) = 0.0715260[/tex]
[tex]\mathbf{\text{Absolute uncertainty} (\%) \simeq 0.07}[/tex]
Finally:
[tex]\mathbf{\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}= 0.88 \pm (0.07) \pm 8\%}[/tex]
At 40 degrees Celsius CH2O2(aq) will decompose according to the following reaction:
2H2O2(aq) ----- 2H2O(l) + O2(g)
The following data were collected for the concentration of H2O2 at various times.
Times(s) [H2O2](M)
0 1.000
2.16x10^4 0.500
4.32x10^4 0.250
a. Calculate the average rate of decomposition of H2O2 between 0 and 2.16 x 10^4 s. Use this rate to calculate the average rate of production of O2(g) over the same time period.
b. What are these rates for the time period 2.16 3 x10^4 s to 4.32 x 10^4 s?
Answer:
A. Rate of decomposition of H₂O₂ = 2.31 × 10-⁵ M/s
Average rate of production of O₂ = 1.16 × 10-⁵ M/s
B. Rate of decomposition of H₂O₂ = 1.16 × 10-⁵ M/s
Average rate of production of O₂ = 5.8 × 10-⁶ M/s
Explanation:
The rate of a reaction is defined as the number of moles of reactant converted or the product formed per unit time.
Reaction rate = change in the concentration of product or reactant / time taken for the change.
A. i) For the decomposition of H₂O₂, the reaction equation is given below:
2 H₂O₂ (aq) ----> 2 H₂O (l) + O₂ (g)
a. the average rate of decomposition of H2O2 between 0 and 2.16 x 10^4 s is calculated as follows :
Rate of decomposition of H₂O₂ = change in concentration / change in time
Rate of decomposition of H₂O₂ = (0.500 - 1.000) M / (2.16 × 10⁴ - 0) s = 2.31 × 10-⁵ M/s
ii) The mole ratio of O₂ to H₂O₂ = 1 : 2 = 0.5
Average rate of production of O₂ = 0.5 × rate of decomposition of H₂O₂
Average rate of production of O₂ = 0.5 × 2.31 × 10-⁵ M/s = 1.16 × 10-⁵ M/s
B. The rate of decomposition of H₂O₂ for the time period 2.16 3 x10^4 s to 4.32 x 10^4 s is calculated as follows:
Rate of decomposition of H₂O₂ = change in concentration / change in time
Rate of decomposition of H₂O₂ = (0.250 - 0.500) M / ( 4.32 × 10⁴ - 2.16 × 10⁴) s = 1.16 × 10-⁵ M/s
ii) The mole ratio of O₂ to H₂O₂ = 1 : 2 = 0.5
Average rate of production of O₂ = 0.5 × rate of decomposition of H₂O₂
Average rate of production of O₂ = 0.5 × 1.16 × 10-⁵ M/s = 5.8 × 10-⁶ M/s
the volume of a substance must be measured several time during an experiment. which units should be used to measure the volume of the substance
Answer:
Volume is often measured numerically using the International System of Units (SI unit), the cubic meter. for example volume of a cube is measured using a cubic centimeter (cm3), the metric system includes the liter (L) as a unit of volume, where one liter is the volume of a 10-centimeter cube.
Emily spills concentrated sodium hydroxide solution on her lab bench. What she should do first?
Answer:
Explanation: hell noo
Diameter of the Balloon
Before Heat
After Heat
6 centimeters 10 centimeters
Which conclusion is supported by the evidence?
A. Air expands when heated.
B. Air is warmer when heated.
C. The balloon will pop when heated.
D. The balloon contracts when heated.
Answer:
A. air expands when heated.
Explanation:
hope this helps!
Air bags are activated when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. This causes sodium azide (NaN3) to decompose explosively according to the following reaction. 2 NaN3(s) --> 2 Na(s) 3 N2(g) What mass in grams of NaN3(s) must be reacted in order to inflate an air bag to 79.5 L at STP
Answer:
154 g
Explanation:
Step 1: Write the balanced decomposition equation
2 NaN₃(s) ⇒ 2 Na(s) + 3 N₂(g)
Step 2: Calculate the moles corresponding to 79.5 L of N₂ at STP
At STP, 1 mole of N₂ occupies 22.4 L.
79.5 L × 1 mol/22.4 L = 3.55 mol
Step 3: Calculate the number of moles of NaN₃ needed to form 3.55 moles of N₂
The molar ratio of NaN₃ to N₂ is 2:3. The moles of NaN₃ needed are 2/3 × 3.55 mol = 2.37 mol.
Step 4: Calculate the mass corresponding to 2.37 moles of NaN₃
The molar mass of NaN₃ is 65.01 g/mol.
2.37 mol × 65.01 g/mol = 154 g
Fill in the blank to complete the statement
Answer:
I dont get it what words are we using bc I see words on the side just it doesn't make any sense
Calculate the number of representative particles of 0.0391 mol Neon gas.
i need help ASAP !
Answer:
2.35 × 10²² particles
Explanation:
To get the number of particles in a substance, we multiply the number of moles (n) of that substance by Avogadro's number (nA).
That is, we say;
number of atoms = n × 6.02 × 10²³
In this question, Neon gas is said to have 0.0391 moles. The number of atoms in that field.
number of particles = 0.0391 × 6.02 × 10²³
number of particles = 0.235 × 10²³
number of particles = 2.35 × 10²² particles
You are an intermediate product of an industrial process which intends to separate iron from its ore. A well known iron ore is hematite. Which of these ores does not contain iron?
Goethite
Malachite
Siderite
Limonite
Answer:
Malachite
Explanation:
Malachite is a copper carbonate hydroxide mineral, with the equation Cu2CO3(OH)2. This dark, green-joined mineral solidifies in the monoclinic precious stone framework, and frequently shapes botryoidal, sinewy, or stalagmitic masses, in cracks and profound, underground spaces, where the water table and aqueous liquids give the way to synthetic precipitation. So, the answer is malachite. Best of Luck!
Given the equation:
H2O (l)
KNO3(s) ————> KNO3(aq)
As H20(l) is added to KNO3(s) to form KNO3(aq), the entropy of the system…
1. decreases
2. increases
3. remains the same
Answer:
2. increases
Explanation:
...............
Answer:
1
Explanation:
Entropy is decrease when product is formed . because of there is stability in the product side.
what is polarization??
Answer:
I Hope this is clear
Explanation:
Polarization, property of certain electromagnetic radiations in which the direction and magnitude of the vibrating electric field are related in a specified way. polarizing filter.
Answer:
Polarization is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave.
Explanation:
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. A simple example of a polarized transverse wave is vibrations traveling along a taut string (see image); for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string. In contrast, in longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization. Transverse waves that exhibit polarization include electromagnetic waves such as light and radio waves, gravitational waves,[6] and transverse sound waves (shear waves) in solids.
An electromagnetic wave such as light consists of a coupled oscillating electric field and magnetic field which are always perpendicular to each other; by convention, the "polarization" of electromagnetic waves refers to the direction of the electric field. In linear polarization, the fields oscillate in a single direction. In circular or elliptical polarization, the fields rotate at a constant rate in a plane as the wave travels. The rotation can have two possible directions; if the fields rotate in a right hand sense with respect to the direction of wave travel, it is called right circular polarization, while if the fields rotate in a left hand sense, it is called left circular polarization.
Light or other electromagnetic radiation from many sources, such as the sun, flames, and incandescent lamps, consists of short wave trains with an equal mixture of polarizations; this is called unpolarized light. Polarized light can be produced by passing unpolarized light through a polarizer, which allows waves of only one polarization to pass through. The most common optical materials do not affect the polarization of light, however, some materials—those that exhibit birefringence, dichroism, or optical activity—affect light differently depending on its polarization. Some of these are used to make polarizing filters. Light is also partially polarized when it reflects from a surface.
According to quantum mechanics, electromagnetic waves can also be viewed as streams of particles called photons. When viewed in this way, the polarization of an electromagnetic wave is determined by a quantum mechanical property of photons called their spin. A photon has one of two possible spins: it can either spin in a right hand sense or a left hand sense about its direction of travel. Circularly polarized electromagnetic waves are composed of photons with only one type of spin, either right- or left-hand. Linearly polarized waves consist of photons that are in a superposition of right and left circularly polarized states, with equal amplitude and phases synchronized to give oscillation in a plane.
Polarization is an important parameter in areas of science dealing with transverse waves, such as optics, seismology, radio, and microwaves. Especially impacted are technologies such as lasers, wireless and optical fiber telecommunications, and radar.
A sample of flammable liquid is placed into an enclosed cylinder which is then fitted with a movable piston. Initially the cylinder contains a volume of 8.20 L. The sample is ignited producing gas and releasing 427.8 J of energy. To what volume will the cylinder expand to if it must expand against a pressure of 826.1 mmHg. Assume all the energy released is converted to work used to push the piston?
760 mmHg = 1 atm
101.3 J = 1 L atm
Answer:
12.09 L
Explanation:
Step 1: Convert 826.1 mmHg to atm
We will use the conversion factor 760 mmHg = 1 atm.
826.1 mmHg × 1 atm/760 mmHg = 1.087 atm
Step 2: Convert 427.8 J to L.atm
We will use the conversion factor 101.3 J = 1 L.atm.
427.8 J × 1 L.atm/101.3 J = 4.223 L.atm
Step 3: Calculate the change in the volume
Assuming the work done (w) is 4.223 L.atm against a pressure (P) of 1.087 atm, the change in the volume is:
w = P × ΔV
ΔV = w/P
ΔV = 4.223 L.atm/1.087 atm = 3.885 L
Step 4: Calculate the final volume
V₂ = V₁ + ΔV
V₂ = 8.20 L + 3.885 L = 12.09 L
What would have happened to humankind if technology did not exist?
1a. A researcher accidentally spilled some sand into his beaker containing crystalline compound X. Knowing what he did about melting points, he was not worried about obtaining the melting point of compound X with a few grains of sand present. Why
Answer:
See explanation
Explanation:
Many organic compounds have low melting points. This is due to the fact that many of these compounds are non polar.
However, compound X is slightly polar but still has a melting point which is far less than that of sand composed of a high melting point inorganic material.
Since sand has a much higher melting point compared to compound X, the researcher need not be worried that sand was spilled into his beaker.
identify the organ system pictured below and state two functions of this system in the body
Answer:
skeletal system
Explanation:
to create and fliter blood and provide frame-work to the human body and support
1. Determine the volume of SO2 (at STP) formed from the reaction of 96.7 mol FeS2 and 55.0 L of O2 at 358 K and 1.20 atm.
4 FeS2(s) + 11O2(g) 2Fe2O3(s) + 8SO2(g)
Answer:
40.0L of SO2 are produced
Explanation:
To solve this question we need to find the moles of O2 using PV = nRT in order to find the moles. Thus, we can find the limiting reactant and the moles (And volume) of SO2 produced as follows:
Moles O2:
n = PV/RT
n = 1.20atm*55.0L / 0.082atmL/molK*358K
n = 2.25 moles of O2.
Clearly, limiting reactant is O2.
The moles of SO2 produced are:
2.25 moles of O2 * (8mol SO2 / 11mol O2) = 1.6351 moles SO2
Volume SO2:
V = nRT/P
V = 1.6351 moles SO2*0.082atmL/molK*358K / 1.20atm
V = 40.0L of SO2 are produced
la. A man was traveling by sie is allowed a maximum of 20kg luggage. The man
weighing 3.5kg, 15kg.2kg and 15kg
Find the excess weight of his luggage.
Express the excess weight as a percentage of the maximum weight allowed
Answer: The excess weight of the luggage is 15.5 kg and its percentage is 77.5%
Explanation:
Given values:
Maximum amount of luggage allowed = 20 kg
Amount of luggage man is carrying = [3.5 + 15 + 2 + 15] kg = 35.5 kg
Excessive weight of the luggage carried = Amount of luggage carrying - Maximum amount of luggage allowed
Excessive weight of the luggage carried = [35.5 - 20] = 15.5 kg
To calculate the percentage of excess weight, we use the equation:
[tex]\% \text{excess weight}=\frac{\text{Excess weight carried}}{\text{Maximum allowed}}\times 100[/tex]
Putting values in above equation, we get:
[tex]\% \text{excess weight}=\frac{15.5kg}{20kg}\times 100\\\\\% \text{excess weight}=77.5%[/tex]
Hence, the excess weight of the luggage is 15.5 kg and its percentage is 77.5%
