Pls tell me the answers for the ones that aren’t answered
Answer:
2 - B, 5 - D, 6 - A
Explanation:
2 - Penicilin was actually discovered on accident!
5 - Microbes were discovered around the mid-1600s
6 - Choice A seems to be correct here, noting that the answers of C and D are marked out and B seems a bit far-fetched (from my current knowledge)
1. Which of the following surfaces does NOT absorb moisture? *
OCardboard
O Metal
Magazine cover
Rough wood
Metal of the following surfaces does NOT absorb moisture.
The correct option is B.
How would you define moisture?The presence of a liquid, things like water, even in minute amounts, is referred to as moisture. Examples of locations where small amounts of water can be found include the air (humidity), foods, and some commercial goods. The amount of water vapor in the atmosphere is also alluded to as moisture.
What causes moisture?Warm, moist weather that comes in touch with a cool surface, such uninsulated cold water mains, causes moisture to condense into water droplets. Numerous other represent the lowest including cooking, taking a bath, drying clothing, washing the dishes, and others also release moisture into the air.
To know more about Moisture visit:
https://brainly.com/question/14894449
#SPJ13
The complete question is -
Which of the following surfaces does NOT absorb moisture? *
A-Cardboard
B- Metal
C-Magazine cover
D-Rough wood
if a compound rotates plane-polarized light in a direction, the compound is called dextrorotatory, and is labeled d or . rotation for an levorotatory compound is labeled l or
If a compound rotates plane-polarized light in a clockwise direction, the compound is called dextrorotatory, and is labeled d
If a compound rotates plane-polarized light in a anti- clockwise direction, the compound is called levorotatory compound is labeled as l.
An enantiomers rotate the plane polarized light in clockwise direction or positive direction is called dextrorotatory. given as [(+), d- ]. while enantiomers that rotates plane polarized light in anti - clock wise direction or negative direction is called levorotatory compound . given as [ (-) , l-].
Thus, If a compound rotates plane-polarized light in a clockwise direction, the compound is called dextrorotatory, and is labeled d
If a compound rotates plane-polarized light in a anti- clockwise direction, the compound is called levorotatory compound is labeled as l.
To learn more about plane polarized light here
https://brainly.com/question/16185241
#SPJ1
A 10.2 g block of tungsten has an original temperature of 6.24°C and a specific heat of 0.134 J/g∙°C. What will be the final temperature of this metal if 14.1327 J of heat energy are added?
The final temperature of metal if 14.1327 J of heat energy is added is 289.57 K which is in relation with specific heat.
How is temperature related to specific heat calculated?Specific heat is calculated by the formula,
Q=mcΔT
In the given problem, Q=14.1327 J, m=10.2 g ,initial temperature=279.24 K
substituting these values in the given equation,
T₂=395.7979/1.3668= 289.57 K.
Specific heat is defined as the amount of heat required to raise the temperature of one gram of a substance by 1 degree Celsius. From specific heat formula, specific heat of any material its mass and gain and loss in temperature can be obtained.
Learn more about specific heat, here:
https://brainly.com/question/21041726
#SPJ1
Takisha conducted an experiment to determine the effect of salt on the boiling point of water. She measured the boiling points of 100 ml of water with salt added in 5 g increments. As a control, she also recorded the temperature of water with no salt added. What is the purpose of this control?.
The control provides a reference value for comparison to samples in which a variable is changed.
What effect does salt have on the experiment with water boiling point?Giddings said that the presence of salt makes it more difficult for water molecules to escape from the pot and transition into the gas phase, which occurs when water boils. Salted water has a higher boiling point as a result.What happens if you experiment with adding salt to water?When salt is added to water, the water becomes denser. Salt provides bulk to the water as it dissolves in it (more weight to the water). By making the water denser, more items that would normally sink in fresh water can float on the surface.What does salt and water come to?Since salt water heats up more quickly and reaches its boiling point first, it will boil more quickly than pure water. When pure solvent (in this case, water) and a dissolved material (salt) are combined to form a solution, boiling elevation point occurs (the salt water).To learn more about boiling point of water visit:
https://brainly.com/question/1416592
#SPJ9
What is the resistance of a light bulb if a potential difference of 120 V will produce a current of 0.5 A in the bulb?
0.0042
0.5
60
240
Answer:
120/0.5
=240ohms
5. How many different types of atoms are in oxytocin?
Answer:
Oxytocin is a peptide of nine amino acids (a nonapeptide).
Explanation:
Answer:Oxytocin is a peptide of nine amino acids (a nonapeptide). The sequence is cysteine - tyrosine - isoleucine - glutamine - asparagine - cysteine - proline - leucine - glycine (CYIQNCPLG).
Explanation:
Carbon contains six electrons and has a mass number of 12. How many neutrons does it contain?
Answer:
6 Neutrons
Explanation:
The number of Protons/Electrons (Protons and electrons are proportional to each other), added with the number of the neutrons that the atom has always equals the mass of the atom.
This claim can be represented with this formula
Protons/Electrons + Neutrons = Atomic Mass
Electrons = 6
Atomic Mass = 12
6(Electrons) + Neutrons = 12(Atomic Mass)
Neutrons = 12 - 6
Neutrons = 6
Therefore, the amount of Neutrons in a carbon molecule are 6
Particles with different charges:
a
are drawn toward each other
b
move closer together
c
attract each other
d
all of the above
Answer:
Your answer is D. All of the above
Explanation:
They are all the same answers just worded differently.
a. the polarities of the bonds must not cancel each other out. b. all of the bonds must be polar. c. there must be at least one nonbonding pair of electrons. d. the molecule must be symmetrical. e. double or triple bonds do not count. f. all of the bonds must be nonpolar. g. all of the terminal atoms around a central atom must have different identities. h. at least one bond must be polar.
For polar molecules :
a) The polarities of the bonds must not cancel each other out is True.
b) All of the bonds must be polar is false. if we have one polar bond the molecule is polar.
c) there must be at least one nonbonding pair of electrons is false.
d) the molecule must be symmetrical is False.
e) double or triple bonds do not count is false
f) all of the bonds must be nonpolar is false.
g) all of the terminal atoms around a central atom must have different identities is False.
h) at least one bond must be polar is true.
To learn more about polar molecule here
https://brainly.com/question/11405437
#SPJ1
For each of the following elements, use the periodic table to give the chemical symbol, atomic number, and the group number of each element, and to specify whether each element is a metal, metalloid, or nonmetal.
Rubidium b. germanium c. Magnesium
d. Titanium e. iodine f. Strontium
a) Rubidium: It is a chemical element with chemical symbol Rb.
Atomic no.: 37
Group: group 1 and first Alkali metal in the group to have density higher than water.
Discovery: Robert Bunsen and Gustav Kirchhoff
b) Germanium: It is a chemical element with the chemical symbol Ge.
Atomic no.: 32
Group: Group 14 Carbon group, a grayish white metalloid in the carbon group.
Discovery: Clemens Winkler
c) Magnesium: It is a chemical element with a chemical symbol of
Atomic no. : 12
Group: group 2(llA) of the periodic table and the chemical properties with the other five alkaline earth metals.
Discovery: Joseph Black
d) Titanium: It is a chemical formula with a chemical symbol of Ti
Atomic no. : 22
Group : group 4 (IVb) of the periodic table a silver grey white metallic appearance.
Discovery : William Gregor
e) Iodine : Iodine is a chemical element with a chemical symbol I.
Atomic no. : 53
Group: group 7A of the periodic table, which is a non metallic at a standard conditions.
Discovery: Bernard Courtois
f) Strontium: It is a chemical element with the symbol Sr.
Atomic no. : 38
Group : group 2(alkaline earth metal) which is a soft silver white yellowish metallic element.
Discovery: William Cruickshank
Refer to the attached Periodic Table and link for further information,
https://brainly.com/question/2467916?referrer=searchResults
when 4.14 moles of ibr gas is initially injected into a 1 l container at 150 c, the kc for this reaction is 8.5 calculate the equilibrium concentration of i2
By using the expression for the equilibrium constant for the reaction and solving the appropriate quadratic equation, we can calculate that the equilibrium concentration of iodine will be 1.77 M.
The balanced reaction equation for this reaction looks like this:
[tex]2 IBr[/tex] → [tex]I_{2}+Br_{2}[/tex]
The expression for the equilibrium constant will look like this:
[tex]K_{c} =\frac{[I_{2} ][Br_{2} ]}{[IBr]^{2} }[/tex]
Because all the volumes are the same, we can just use the moles of all reaction components instead of concentrations. Now, because there was no iodine or bromine when the reaction began, all iodine and bromine present at equilibrium are formed by IBr decomposition, their concentrations will be the same (X). The concentration of IBr will be reduced by 2X, so we can plug that into the equilibrium constant expression:
[tex]8.5=\frac{X^{2} }{(4.14-2X)^{2} }[/tex]
We transform this expression to get a quadratic equation:
33X² - 140.76X + 145.6866 = 0
When we solve for X, one solution is 2.49 M (which is impossible, because 4.14 moles of IBr can create a maximum of 4.14 mol / 2 = 2.07 mol of iodine), and the other (correct) solution is 1.77 M.
You can learn more about the equilibrium constant here:
brainly.com/question/19669218
#SPJ4
What is the
Compound name for NaCrO4
The relative abundance and atomic masses are: 30.8% for mass of 64.93u
Answer:
The element copper has naturally occurring isotopes with mass numbers of 63 and 65. The relative abundance and atomic masses are 69.2% for mass = 62.93 amu, and 30.8% for mass = 64.93 amu.
The electron configurations of two unknown atoms are shown.
Electron Configuration
Based on the electron configuration of each atom, what is the number of valence electrons for each atom?
a Atom X = 1; Atom Y = 1
b Atom X = 1; Atom Y = 7
c Atom X = 10; Atom Y = 10
d Atom X = 11; Atom Y = 17
Answer:
b Atom X = 1; Atom Y = 7
Explanation:
a valence electron is an electron in the outer shell
So X has 1 in outer shell
Y has 7 in outer shell
a rigid plastic container holds 6.38 l of methane gas at 127 torr pressure when the temperature is 26.0 degrees celsius. how much pressure will the gas exert if the temperature is raised to 43.1 degrees celsius?
A pressure of 210.5 torr will be exerted by the gas if the temperature is raised to 43.1°C.
What are pressure and temperature?Temperature as we have been learning from childhood is the degree of hotness or coldness.Pressure is the force exerted per unit area that is the force you exert on a given surface.By using the gas equation that is PV=NRT we can solve his question to know the pressure exerted when the temperature is changed.According to Charles's law P₁/T₁ = P₂/T₂
Given, P₁ is 127 torr and T₁ is 26°C and T₂ is 43.1°C.
127/ 26 = P₂/ 43.1
P₂ = (127 × 43.1) / 26
P₂ = 5473.7 / 26
P₂ = 210.5 torr
To know more about pressure and temperature visit:
https://brainly.com/question/2060803
#SPJ9
5. If root growth is related to gravity, then roots will always turn toward the earth
regardless of a seed's orientation.
Independent variable -
Dependent variable -
The root growth is related to gravity as as negative geotropic and positive geotropic with regards to gravity on the roots.
What is root growth and how roots grow with regards to gravity?Root grows in the direction into the soil, as due to gravity in most of the plants.Roots have meristematic activities which led the plants into the soil and makes a strong grip till the plants matures.There are two kind of root growth with regards to gravity that is positive geotropic and negative geotropic.Positive geotropic means root grows towards the gravitational direction.Negative geotropic means root grows opposite to the direction of gravity.Root growth in Rhizopora is negative geotropic that is opposite to the direction of gravity.To know more about root growth visit:
https://brainly.com/question/237871
#SPJ13
3. What units are used to express pressure measurements?
Answer: Pascals (Pa)
Explanation:The SI unit for pressure is pascals (Pa). Other units of pressure include torr, barr, atm, at, ba, psi, and manometric units like mm Hg and fsw. I hope this helped! :) have a good day!
Answer:
Explanation:
Question 1
Put the sentences in order to provide an objective summary of the passage. Not all sentences will be used.
Sentence 1. Laughing reduces stress, improves circulation, and reduces the risk of heart problems.
Sentence 2. Funny books, movies, and friends are an important part of healthy living.
Sentence 3: Laughter therapy provides numerous physical and mental benefits.
Sentence 4: People with heart problems may be less likely to laugh because of those problems.
Sentence 5: Scientific research suggests that laughter has many health benefits.
Sentence 6: Laughter causes the endotheli
A 3.2 L sample of a gas at 2 atm of pressure is expanded until its volume is 5 L. What will be thepressure in atm of the expanded gas sample? Include proper units (abbreviated). Round your answer to two decimal places.
1.28atm
Explanations:According to Boyle's law
P1V1 = P2V2
where
P is the pressure
V is the volume
Given the following
P1 = 2atm
V1 = 3.2L
V2 = 5L
Required
Final pressure P2
Substitute
P2 = P1V1/V2
P2 = 2*3.2/5
P2 = 6.4/5
P2 = 1.28atm
Hence the pressure in atm of the expanded gas sample
Need help finding the moles on this question ?
In areaction, the number of moles consumed and produced have the same ratio as the coefficients on the balanced equation.
So, to calculate the number of moles of any chemical on the reaction given the number of moles of any other, we can use a rule of three.
We put the compound or atom we want on the first column and the one we have information of on the second, and their coefficients on the second row:
We want Al and we have information about Al₂O₃, and their coefficients on the balanced equation are 4 and 2, so:
Al --- Al₂O₃
4 2
Now, we use thise placements to write the equation:
[tex]\frac{n_{Al}}{4}=\frac{m_{Al_2O_3}}{2}[/tex]Where the n stands for the number of moles. Now we solve for Al:
[tex]\begin{gathered} \frac{n_{Al}}{4}=\frac{m_{Al_2O_3}}{2} \\ n_{Al}=4\frac{m_{Al_2O_3}}{2} \\ n_{Al}=2m_{Al_2O_3} \end{gathered}[/tex]And since we know the number of moles of Al₂O₃, we have:
[tex]\begin{gathered} n_{Al_{2}O_{3}}=0.800mol \\ n_{Al}=2n_{Al_{2}O_{3}} \\ n_{Al}=2\cdot0.800mol \\ n_{Al}=1.600mol \\ n_{Al}\approx1.60mol \end{gathered}[/tex]Where the last step we did an approximateion to get to 3 significant figures.
So, the number of moles of Al consumed is 1.60 mol.
An individual cell of an entire multicellular organism may be between 70% and 95% water, moreover, cells
and organisms resist rapid temperature changes. This important characteristic is based on what property of
water?
C. the density of water
D. one water can covalently bond to another
water molecule
A strong ionic bonds between water
molecules
B. the specific heat of water
B. the specific heat of water
What is a multicellular organism?A multicellular organism is an organism that consists of many cells. The term "multi" is technically used to refer to something that is more than one, so "multicellular" means more than one.
Multicellular organisms evolve through cell specialization and division of labour. Cells become efficient at one process and depend on other cells to carry out different processes. All the cells work in coordination to ensure the proper functioning of the body.
To learn more about the multicellular organism, visit;
https://brainly.com/question/941766
#SPJ13
A typical frostless refrigerator uses 655 kWh of energy per year in the form of electricity. Suppose that all of this electricity is generated at a power plant that burns coal containing 3. 1% sulfur by mass and that all of the sulfur is emitted as SO2 when the coal is burned.
If all of the SO2 goes on to react with rainwater to form H2SO4 , what mass of H2SO4 is produced by the annual operation of the refrigerator? ( Hint : Assume that the remaining percentage of the coal is carbon and begin by calculating ΔH∘rxn for the combustion of carbon. )
The annual operation of the refrigerator produces 6835.5 g of sulfuric acid. This calculation is made assuming that the enthalpy of combustion for sulfur is equal to the enthalpy of combustion for carbon.
First, we are going to transform 655 kWh into kilojoules. Because 1 kWh = 3.6e6 J = 3600 kJ, that means that a typical frostless refrigerator uses 655 * 3600 kJ = 2358000 kJ of energy on a yearly basis.
The enthalpy of combustion for carbon (or enthalpy of carbon dioxide formation) is -393 kJ/mol. That means that we can calculate the number of moles of carbon needed to produce 2358000 kJ of energy.
2358000 kJ / 393 kJ/mol = 6000 mol of carbon
Because the molar mass of carbon is 12 g/mol we need
6000 mol * 12 g/mol = 72000 g of carbon
If 3.1% of this carbon is actually sulfur, then we will burn 0.031 * 72000 g = 2232 g of sulfur during one year. The molar mass of sulfur is 32 g/mol, which means we transformed 2232 g / 32 g/mol = 69.75 mol of sulfur into sulfur dioxide and further into sulfuric acid. Because 1 mol of sulfur is needed to produce 1 mol of sulfuric acid, we produced 69.75 moles of sulfuric acid.
The molar mass of sulfuric acid is 98 g/mol, so over the course of one year, we produced 69.75 mol * 98 g/mol = 6835.5 g of sulfuric acid.
You can learn more about sulfuric acid here:
brainly.com/question/1107054
#SPJ4
ammonia, an important source of fixed nitrogen that can be metabolized by plants, is produced using the haber process in which nitrogen and hydrogen combine.n2(g) 3h2(g) → 2nh3(g)how many grams of nitrogen are needed to produce 325 grams of ammonia?
Using a stoichiometric calculation, it was determined that 178.43 grams of nitrogen are needed to produce 325 grams of ammonia.
We can use a simple stoichiometric proportion to calculate this. First, we write the reaction:
[tex]N_{2} + 3H_{2}[/tex] → [tex]3 NH_{3}[/tex]
We can see that 1 mole of nitrogen produces 2 moles of ammonia.
Nitrogen's molar mass is 2 * 14 = 28 g/mol.
The molar mass of ammonia is 14 + 3 * 1 = 17 g/mol.
Based on this and the reaction equation, we can say that 28 grams of nitrogen produce 3 mol * 17 g/mol = 51 g of ammonia.
Now, we make a proportion:
28 g of nitrogen : 51 g of ammonia = X : 325 g of ammonia
X = 28 g of nitrogen * 325 g of ammonia / 51 g of ammonia = 178.43 g of nitrogen
You can learn more about stoichiometry here:
brainly.com/question/9743981
#SPJ4
What is the most toxic chemical ever?
Answer: Botulinum toxin
Explanation: yes
Answer: Botulinum toxin
Explanation:
are among the worst chemicals ever discovered. Botulinum toxins can cause respiratory and muscle paralysis by blocking nerve functioning. Foodborne botulism, newborn botulism, wound botulism, inhalation botulism, and various forms of intoxication are all examples of human botulism.
What mass of Silver hydroxide (an insoluble base) is needed to neutralize 98.35 mL of 0.5417M Acetic Acid?
A mixture of three gases (ar, ne, and co2) has a total pressure of 1.2 atm. if the mixture of gases is composed of 25.0 g of each gas, what is the partial pressure of ne?
Answer: The first task is to determine the moles of each gas present. This makes use of the molar masses of each gas. The molar masses are:
Molar Mass Ar = 39.948 grams per mole
Molar Mass Ne = 20.1797 grams per mole
Molar Mass CO2 = 44.01 grams per mole
Calculating for the moles of each gas present, we get.
(In the png attatched.)
If this helped you please consider marking this as the Brainliest Answer, if i make it to 10, I can be promoted to an expert. How? - Once you get more than 1 answer of a question. A message is shown above each answer that is "Mark as brainiest". Click on the option to mark it the best answer. Thank you!
which of the folllowing is the Arrhenius definition of an acidl
Answer:
Arrhenius defined an acid as a compound that increases the concentration of hydrogen ion (H +) in aqueous solution. Many acids are simple compounds that release a hydrogen cation into solution when they dissolve.
16.) If you have 54 mg of a substance that has a density of 1.2 g/mL how many mL of the substance do you
have?
The volume of the substance with mass of 54mg and density of 1.2g/mL will be 0.045 mL.
How much "stuff" is contained in a specific quantity of space is determined by its density. For instance, a block of the harder, lighter element gold (Au) will be denser than a block of the heavier element lead (Pb) (Au). Styrofoam blocks are less dense than bricks.
Mass per unit volume serves as its definition.
We know that, Density = mass of substance / volume of substance
Given,
mass = 54 mg = 0.054 g
Density = 1.2g/mL
D = m/ v
1.2 = 0.054 / v
1.2 × v = 0.054
v = 0.054 / 1.2
v = 0.045 mL
To know more about density visit the link:
https://brainly.com/question/15164682?referrer=searchResults
#SPJ9
A sealed weather balloon contains 10.0 L of helium gas at 5 °C. What is the volume of helium in the weather balloon at 15 °C?
Volume of the helium in weather balloon at 15 °C with initial volume of 10L and temperature of 5 °C is 30 L
Given that, Initial volume (V1) = 10 L
Initial Temperature (T1) = 5 °C
Final Temperature (T2) = 15 °C
By gas law,
V1 / V2 = T1 / T2 (Pressure constant)
10 / V2 = 5 / 15
V2 = (15 / 5) * 10
V2 = 3 * 10
V2 = 30 L
Thus, the volume of helium in the weather balloon at 15 °C is 30 L
To know more about Gas law
https://brainly.com/question/12667831
#SPJ1
What volume of each of the following bases will react completely with 23.00 mL of 0.500 M HCl?
(a) 0.100 M NaOH
mL
(b) 0.0500 M Ba(OH)2
mL
(c) 0.250 M KOH
mL
The volume of each of the following bases will react completely with 23.00 mL of 0.500 M HCl are given below ,
( a ) 28 ml
( b ) 230 ml
( c ) 46 ml
The volume of each of the following bases will react completely with 23.00 mL of 0.500 M HCl can be calculated as ,
Formula used : [tex]M_{1} V_{1}[/tex] = [tex]M_{2} V_{2}[/tex] ( 1 )
( a )
Given
[tex]M_{1}[/tex] = 0.500 M
[tex]M_{2}[/tex] = 0.100 M
[tex]V_{1}[/tex] = 23.00 mL
[tex]V_{2}[/tex] = ?
Now putting the all given data in equation ( 1 ) we get the value of volume
0.500 M × 23.00 mL = 0.100 M × [tex]V_{2}[/tex]
[tex]V_{2}[/tex] = 0.500 M × 23.00 mL / 0.100 M = 28 ml
( b )
Given
[tex]M_{1}[/tex] = 0.500 M
[tex]M_{2}[/tex] = 0.0500 M
[tex]V_{1}[/tex] = 23.00 mL
[tex]V_{2}[/tex] = ?
Now putting the all given data in equation ( 1 ) we get the value of volume
0.500 M × 23.00 mL =0.0500 M × [tex]V_{2}[/tex]
[tex]V_{2}[/tex] = 0.500 M × 23.00 mL / 0.0500 M = 230 ml
( b )
Given
[tex]M_{1}[/tex] = 0.500 M
[tex]M_{2}[/tex] = 0.250 M
[tex]V_{1}[/tex] = 23.00 mL
[tex]V_{2}[/tex] = ?
Now putting the all given data in equation ( 1 ) we get the value of volume
0.500 M × 23.00 mL = 0.250 M × [tex]V_{2}[/tex]
[tex]V_{2}[/tex] = 0.500 M × 23.00 mL / 0.250 M = 46 ml
learn about volume here ,
https://brainly.com/question/14710169
#SPJ1