Answer: number 9 is: Measurements are fundamental to experimental science. Number 10 is: To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements. Number 11 is: Measurements must always be reported to the correct number of significant figures because calculated answers often depend on the number of significant figures in the values used in the calculation. Number 12 is: Usually a calculated answer cannot be more precise than the least precise measurement from which it was calculated. Number 13 is: 125.7−124.1=1.6 125.7 − 124.1 = 1.6 degrees Celsius. Number 14 is: a. 11 soccer players- 2 SF b. 0.070 020 meter- 5 SF c. 10,800 meters- 5 SF
d. 5.00 cubic meters- 1 SF.
Number 15 is: A)
Number of significant figures = 2
B)
Number of significant figures = 2
C).
Number of significant figures = 1
D).
Number of significant figures = 3
E).
Number of significant figures = 3
Explanation:
which is an expression of molality
Answer:The formula for molality is m = moles of solute / kilograms of solvent.
Explanation:
what is the basis for the classification of organic compounds?
Answer:
organic compounds are classified based on functoin group
Explanation:
functional group is part of molecule or compound that determine the properties of that molecule or compound.
In chemistry, organic compounds are substances that have a covalently linked carbon atom. These compounds are classified based on the functional group and structures.
What are organic compounds?Organic compounds are said to be the compounds that have the presence of the carbon atom/s linked to the other atoms including nitrogen, oxygen, and hydrogen through a covalent bond.
The organic compounds are classified based on their structures and functional groups attached to their side chains. The functional groups include alkynes, alkenes, alcohols, carbonyl, nitriles, amines, etc.
The compounds can also be categorized based on the open or closed chain structures that can be homocyclic or heterocyclic. Further, the compounds can be aromatic or alicyclic.
Therefore, organic compounds are classified based on their functional groups and structures.
Learn more about organic compounds here:
https://brainly.com/question/13245955
#SPJ2
What is the electron configuration for manganese
Electron configuration for manganese is [Ar]3d⁵4s² and electron configuration is the distribution of electrons of an atom or molecule
The electronic configuration of an element is a symbolic notation of the manner in which the electrons of its atoms are distributed over different atomic orbitals and atomic number of manganese is 25 then electronic configuration [Ar]3d⁵4s² manganese is a chemical element with the symbol Mn and it is a hard, brittle, silvery metal, often found in minerals in combination with iron and atomic mass is 55.93 and we write electronic configuration is 1s²2s²2p⁶3s²3p⁶4s²4d⁵ called as electronic configuration of manganese
Know more about electron configuration
https://brainly.com/question/15489236
#SPJ1
. Both element K and element L are found in period 3 of the periodic
table. If K is in group 13 while L is in group 15, which of the two
has a greater atomic number? Explain.
Answer: L element has greater atomic number.
Explanation:
The periodic table contains vertical columns called as groups and horizontal rows called as periods.
Period 3 contains 8 elements which are sodium, magnesium , aluminium , silicon , phosphorous , sulphur, chlorine and argon.
K element which belongs to group 13 is aluminium with atomic number of 13 . L element which belongs to group 15 is phosphorous with atomic number of 15.
Thus L element has greater atomic number.
Explain why, in a balanced chemical equation C + O2 CO2, we know that 1 gram of C will not react exactly with 1 gram of O2.
Answer:
See the answer below
Explanation:
From the equation, 1 mole of C requires 1 mole of O2 for a balanced reaction.
1 g of C will not exactly react with 1 g of O2 because the 1 g of each of the reactants contain different amounts of the substance.
The amount (in moles) of a substance is the mass of that substance divided by the molar mass.
Hence, 1 g of C will contain 1/12 moles of the substance while 1 g of O2 will contain 1/32 moles of the substance.
Why Are Microorganism's Used to separate waste products from water?
Answer:
Untreated water from rivers, lakes, ponds, springs, or streams is likely to contain unsafe levels of infectious microorganisms, and drinking it may cause illness.
Explanation:
Which of the following definitions best describes a parallel of latitude?
a--A line that is drawn horizontally around the earth and is parallel to the Prime Meridian.
b---A line that is drawn vertically down the earth and is parallel to the equator.
c--A line that is drawn vertically down the earth and is parallel to the Prime Meridian.
d--A line that is drawn horizontally around the earth and is parallel to the equator.
The statement that express the definitions of parallel of latitude as regards this question is :A: A line that is drawn horizontally around the earth and is parallel to the Prime Meridian.
A circle of latitude can be regarded as a line of latitude that found on Earth, it can be explained as abstract (east–west) small circle which connect all locations around Earth and this is been done at a particular latitude coordinate line.It is drawn horizontally and usually parallel to Prime Meridian.Therefore, option A is correct.
Learn more at:
https://brainly.com/question/20511150?referrer=searchResults
2. The combustion of octane is -47.5 kJ/g.
a. Write the reaction for the combustion of octane.
b. What is the value of the enthalpy of combustion for octane per mole?
c. If the enthalpy of combustion was written with the reaction, what value would be
used?
The enthalpy of combustion per mole is -5397.7 kJ/mol.
What is combustion?The term combustion refers to a reaction in which a substance is burnt in oxygen. Now we know that octane is a hydrocarbon and its combustion follows the general equation for the combustion of hydrocarbons.
[tex]2C_{8}H_{18} (g) + 25O_{2} (g)---- > 16CO_{2} (g) + 18H_{2} O(g)[/tex]
Given that the number of moles in one gram of octane is obtained from;
1g/114 g/mol = 0.0088 moles
If the burning of 0.0088 moles of octane produces -47.5 kJ
Burning of 1 mole of octane would produce 1 mole * -47.5 kJ/0.0088 moles
= -5397.7 kJ/mol
We can now write is as;
[tex]2C_{8}H_{18} (g) + 25O_{2} (g)---- > 16CO_{2} (g) + 18H_{2} O(g)[/tex] ΔH = -5397.7 kJ/mol
Learn more about combustion:https://brainly.com/question/15117038
#SPJ1
ASAP pleaseee and Thankyou
Using the geologic concept of plate boundaries, compare and contrast the formation of the Andes Mountains,
Himalayan Mountains, the islands of Japan, Iceland, and the San Andreas area of California?
Plz I need help
How many atoms are in 10.4 mol of CI?
Answer:
there are two atoms
1. hydrogen
2.and water
Answer:
[tex]\boxed {\boxed {\sf 6.26 \times 10^{24} \ atoms }}[/tex]
Explanation:
To convert from moles to atoms, we must use a number called Avogadro's Number which is:
[tex]6.022\times10^{23}[/tex]
This number tells us the amount of atoms in a mole.
[tex]1 \ mole = 6.022\times10^{23} \ atoms[/tex]
To convert from moles to atoms, we must multiply Avogadro's number by the amount of moles.
We know there are 10.4 moles of Chlorine. Multiply 10.4 (molar amount) by 6.022 * 10²³ (Avogadro's Number)
[tex]10.4 \ mol *\frac{6.022\times10^{23} \ atoms }{ 1 \ mole}[/tex]
[tex]10.4 * 6.022\times10^{23} \ atoms[/tex]
[tex]1 \ mole = 6.022\times10^{23} \ atoms[/tex]
[tex]6.26288 \times 10^{24} \ atoms[/tex]
Let's round to 3 significant figures, because the original measurement 10.4, has 3 sig figs (1, 0, and 4)
For the number 6.26288, 3 significant figures is the hundredths place. The 2 in the thousandth place tells us to keep the 6 in the hundredths place.
[tex]6.26 \times 10^{24} \ atoms[/tex]
There are about 6.26 × 10²⁴ atoms in 10.4 moles of chlorine.
define thermal and electrical conductivity, solubility, magnetism, melting and boiling points
Answer:
thermal conductivity: the rate at which heat is transferred by conduction through a unit cross-section area of a material, when a temperature gradient exits perpendicular to the area
electrical conductivity: the measure of the amount of electrical current a material can carry or it's ability to carry a current
solubility: the ability to be dissolved, especially in water
magnetism: a physical phenomenon produced by the motion of electric charge, resulting in attractive and repulsive forces between objects
melting point: the temperature at which a given solid will melt.
boiling point: the temperature at which a liquid boils and turns to vapor
Explanation:
hope this helps :D pls mark brainliest :D
mass number is the number of protons and neutrons in the nucleus of an isotope . how many protons in an oxygen-18 atom ?
Answer: Oxygen - 18 atom contains 8 protons.
Explanation:
The number of protons is the same as the atomic number. In isotopes, only the neutrons vary, but the protons always remain the same.
C6H12O6 + 6O2 → 6CO2 + ? H2O + energy
Whats the answer? I really don't know,
Answer: C. 6
Explanation:
According to the Law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reaction for photosynthesis is :
[tex]C_6H_{12}O_6+6O_2\rightarrow 6CO_2+6H_2O+energy[/tex]
Thus the coefficient of water is 6.
A solution is made
by dissolving
29 g of sodium lithium chloride
in water to a final volume of
202 mL solution.
What is the weightweight % or percent by mass of the somute
percent by mass of the solute?
Answer:
99.3%
Explanation:
The percent by mass of the solute can be expressed as:
% mass = [tex]\frac{MassSolute}{MassSolute+MassSolvent}[/tex] * 100%And for this problem:
Mass of Solute = Mass of sodium lithium chloride = 29 gMass of Solvent = Mass of WaterSo to calculate the percent by mass first we need to calculate the mass of water, to do so we use its density (1 g/L):
202 mL is equal to (202/1000) 0.202 L.Density water = mass water / volume
1 g/L = mass water / 0.202 LMass water = 0.202 gNow we have all the data required to calculate the % mass:
% mass = [tex]\frac{29g}{29g+0.202g}[/tex] * 100 % = 99.3%Answer: 14.3
Explanation:
lonic Bonding
Why did it require two sodium atoms to Complete
the Na 0 formula unit?
Na has +2 charge and O has -1 charge.
Na has +1 charge and O has -2 charge
Na has -2 charge and O has +1 charge.
Ms. Salis explains to her class that sodium (Na) and chlorine (Cl) atoms bond to make table salt
(NaCl). Which is the best description of table salt? *
A)It is a cell.
B)It is an atom.
C)It is an element.
D)It is a compound
In TEN complete sentences, describe how the LAW OF CONSERVATION applies to the stuff YOU OWN. For example: In real life, can new XBOXs be magically created, or garbage magically destroyed? Why? You are made up of recycled atoms. Where did these atoms come from? *
Answer:
Both the initial and final substances are composed of atoms because all matter is composed of atoms. According to the law of conservation of matter, matter is neither created nor destroyed, so we must have the same number and type of atoms after the chemical change as were present before the chemical change.
Explanation:
The atoms that make up your body were produced inside a star and have ... I read once that atoms get recycled so much through the planet that each of ... from William Shakespeare, but I do know this: All of us come from stars. ... If you have gold fillings in your teeth, those atoms came from a star explosion.
What is the mass of 0.78 mol Mg(NO3),? Make sure to round to the correct number of sig figs and to include the unit in your final answer
Answer:
67.08 g
Explanation:
you firts write what u know
then u calculate the molar mass of the salt
then according to the formula mass= number of mols × molar mass you find the mass
m= mass
n= number of mol
M= molar mass i hope this helps
What happens when a wave hits an object?
the wave is reflected
the wave continues on
the wave is interfered with
the wave stops
calculate the mole fraction of alcl3 in a solution made by dissolving 195 g of alcl3 in 240 ml of water
The mole fraction of 195 g AlCl3 in 240 mL of water is 0.099.
Mole fraction is the ratio of the number of moles of a particular component to the total number of moles in the mixture. To determine the mole fraction of AlCl3, the mass of AlCl3 will be converted to moles and the number of moles of water must be determined. Since the amount of water used is expressed in volume, we will be using the density of water to determine the mass of water for a given volume.
Solving for the moles of AlCl3:
moles AlCl3 = mass AlCl3 / molar mass of AlCl3
moles AlCl3 = 195 g / 133.33 g/mol
moles AlCl3 = 1.4625 mol
Solving for moles of water:
A commonly used density of water is 1 g/mL.
240 mL of water * (1 g/mL) = 240 g of water
moles water = mass water / molar mass water
moles water = 240 g / 18.02 g/mol
moles water = 13.32 mol of water
Mole fraction = mol AlCl3 / ( mol AlCl3 + mol water)
Mole fraction = 1.4625 / {1.4625 +13.32)
Mole fraction of AlCl3 is 0.099
To learn more about mole fraction calculation, please refer to https://brainly.com/question/14498215.
#SPJ4
. If the half-life of cesium-133 is 30 years, how much of a 600g sample of cesium-133 will be left after
150 years
Answer:
Caesium (55Cs) has 40 known isotopes, making it, along with barium and mercury, one of the elements with the most isotopes. The atomic masses of these isotopes range from 112 to 151. Only one isotope, 133Cs, is stable. The longest-lived radioisotopes are 135Cs with a half-life of 2.3 million years, ... It constitutes most of the radioactivity still left from the Chernobyl accident ...
HELP PLEASE
What makes up most of an
atom's volume, and where is it located?
Answer:Accounting for the sizes of protons, neutrons, and electrons, most of the volume of an atom—greater than 99 percent—is, in fact, empty space. ... The electrons that surround all atoms are negatively charged and cause atoms to repel one another, preventing atoms from occupying the same space.
Explanation: hope this helped
You have used 2. 6×102 L of distilled water for a dialysis patient. How many gallons of water is that?
By unit conversion, the distilled water for dialysis in gallons is 68.69 gallons.
We need to know about unit conversion to solve this problem. The unit conversion can be used to convert a unit to another unit. It can be defined as
a = xb
where a is unit a, b is unit b and x is the constant of conversion.
From the question above, we know that
V = 2.6 x 10² liters
The unit conversion that we used is (1 gal = 3.785 liters)
V = 2.6 x 10² liters
V = 2.6 x 10² / 3.785 gal
V = 68.69 gallons
Hence, the distilled water for dialysis in gallons is 68.69 gallons.
Find more on unit conversion at: https://brainly.com/question/4158962
#SPJ4
ASAP pleaseee and Thankyou
Answer:
I know the answer, but it is hard to explain
Explanation:
yIt easy u but the single letter in the outside boxes. Then u but the one in the middle box. But the BB in one corner. then but bb on the opposite corner. Then but Bb on the other box.
Answer:
father.....Bb
mother.....bb
offspring, 50%Bb brown eyes ,50%bb blue eyes
Prompt
The skeletal system, the muscular system, and the nervous system all work together. Explain one link between the skeletal system and the muscular system, between the skeletal system and the nervous system, and between the muscular system and the nervous system.
Answer:
They work in unision
Explanation:
The skeletal system is the framework our muscular system is attached to. The muscular system also allows the bones to move through contracting and extending. Although both would be useless without the nervous which sends impulses that tell the muscles to contract and extend.
Answer:
The person above is correct!
Explanation:
It graded it 100%.
if the protons are 6 the neutrons are 6 and the electrons are 6 what is the total charge
Answer:
0
General Formulas and Concepts:
Chemistry - Atomic Structure
Protons have a positive (+) charge.Neutrons have a neutral (0) charge.Electrons have a negative (-) charge.Explanation:
Step 1: Define
6 Protons
6 Neutrons
6 Electrons
Step 2: Determine charges
6 Protons = + 6 charge
6 Neutrons = 0 charge
6 Electrons = - 6 charge
Step 3: Determine overall charge
+6 + 0 + -6 = 0
How many sucrose molecules will be in 250 grams
We will need to know Avogadro's number and the molar mass of sucrose for this problem to do dimensional analysis.
Avogadro's number: 6.022 × 10²³ moleculesMolar mass of sucrose: 342.2965 g/mol250g × [tex]\frac{1 mol}{342.297g}[/tex] × [tex]\frac{6.022 * 10^{23} molecules}{1 mol}[/tex] = 4.398 molecules
There are 4.398 sucrose molecules in 250 grams of sucrose.
Which test uses color change to reveal oil-based paints?
mass spectometry
gas chromatography
potassium hydroxide test
ethanol test
Answer:
potassium hydroxide test
Explanation:
The test that uses color change to reveal oil-based paints is the potassium hydroxide test. The correct option is c.
What is a potassium hydroxide test?The KOH (potassium hydroxide) approach is used to test for yeast in specimens. Potassium hydroxide acts as an enzymatic agent, breaking down detritus in a specimen, such as epithelial cells and WBCs, allowing yeast or pseudohyphae to be seen.
The potassium hydroxide prep test is used to detect fungal diseases on the skin or in the nails. A scrape of cells from the afflicted area is examined under a microscope for evidence of fungus. The potassium hydroxide skin lesions exam, fungal smear, or skin scraping are other names for the potassium hydroxide test.
Therefore, the correct option is the c, potassium hydroxide test.
To learn more about the potassium hydroxide test, refer to the link:
https://brainly.com/question/18549747
#SPJ2
PLS ANSWER THESE 3 QUESTIONS WHICHEVER YOU KNOW!!
1.For an object at rest, the normal force equals the gravitational force. What is the sum of these forces called?
·ω·
A Net force
B Unbalanced force
C Inertia
D Potential force
2. Which of the following best describes the forces when there are different-sized forces from opposite directions acting on an object?
a Positive
b Negative
c Unbalanced
d Gravitational
3. An object is at rest on a table. The gravitational force is 10 N down, and the normal force is 10 N up. What is the net force?
An object at rest on a table. An arrow pointing down represents 10 newtons of gravitational force. An arrow pointing up represents 10 newtons of normal force.
a 10 N up
b 0 N
c 10 N down
d 20 N up
Answer:
I only know 3 its 0 N because 10-8=2 and 2-2=0
Explanation 10-8=2 2-2=0