Answer:
Friction between the hand and the wood decreased.
Explanation:
The texture of the wood went from rough → smooth! This means friction between the hand and the wood was notably decreased.
According to this prompt, the carpenter used sandpaper against the wood. Sandpaper just so happens to be a very abrasive substance. The sandpaper polished and leveled out the wood which wore all the jutting bits away.- overall, making it much smoother and more pleasant to touch!
Hope I was of assistance! Have a nice day and Spread the Love! <3
Match the terms below to the correct definitions
3. Atom
1. The mass on the periodic table.
b. Electrons
2. Region surrounding the nucleus where electrons are found.
C. Protons
3. Positively charged center of an atom.
d. Neutrons
4. Particles that differ in number between isotopes.
e. Electron
cloud
5. Vertical column in the periodic table.
1. Nucleus
6. Positively charged particles in an atom.
R. Quark
7. Negatively charged particles in the outermost energy levels of the electron cloud.
8. Table that organizes the elements by properties.
9. Atoms of the same element that have different masses.
h. Atomic
number
1. Mass number
10. Smallest known particle that makes up protons and neutrons.
j. Average
atomic mass
11. All elements in the same one of these has the same number of energy levels in
their electron cloud.
k. Isotopes
12. The smallest form of matter that still retains the properties of an element.
1. Valence
electrons
13. Negatively charged particles in an atom.
m. Group
14. The sum of protons and neutrons in an atom.
n. Period
15. Represents the identity of an element.
o. Periodic
Table
Answer:
Explanation:
1=i
4=d
5=m
6=c
8=o
9=j
10=a
13=b
14=h
15=l
Theses are the ones i knew
why is lithium used in the body?
Answer:
11
Explanation:
Elements in group to are cold alkaline earth metals what is most similar about alkaline earth metals how many protons and neutrons they have which Chemical properties he have how many total electrons they have which period They have most often found in
Answer:
explanations below
Explanation:
The alkaline earth metals are the 6 chemical elements that can be found in group two of the periodic table. These elements have a lot of properties in common, in the sense that they are generally shiny, reactive at standard temperature and pressure and they are also silvery-white. The elements are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)
These metals have two electrons at their orbits, which can be easily lost to form cations (with charge +2, and an oxidation state of +2)
Below are some of their details
Name: Beryllium
Number of Protons/Electrons: 4
Number of Neutrons: 5
Name: Magnesium
Number of Protons/Electrons: 12
Number of Neutrons: 12
Name: Calcium
Number of Protons/Electrons: 20
Number of Neutrons: 20
Name: Strontium
Number of Protons/Electrons: 38
Number of Neutrons: 50
Name: Barium
Number of Protons/Electrons: 56
Number of Neutrons: 81
Name: Radium
Number of Protons/Electrons: 88
Number of Neutrons: 138
The density of air at STP is 1.285 g/L. Which of the following cannot be used to fill a balloon that will float in air at STP?
NO can't be used to fill a balloon
Further explanationConditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters/mol.
Answer options that need to be added :
a. Ne
b. NO
c. NH₃
d. CH₄
e. HF
will float in air ⇒ element or compound to fill the balloon, its density must be less than < 1.285 g/L
We can use the ideal gas formula ta find density :
[tex]\tt \rho=\dfrac{P.MW}{RT}[/tex]
Because at STP, then the constant value is
[tex]\tt \rho=\dfrac{1~atm\times MW}{0.08205\times 273.15~K}\\\\\rho=0.0446\times MW[/tex]
So that the density is determined from the MW(molecular weight) of each element or compound
a. NeAr = 20.1797 g/mol
[tex]\tt \rho=0.0446\times 20.1797=0.9~g/L[/tex]
b. NOMW=30.006 g/mol
[tex]\tt \rho=0.0446\times 30.006=\boxed{\bold{1.338~g/L}}[/tex]
c. NH₃MW=17.0306 g/mol
[tex]\tt \rho=0.0446\times 17.0306=0.760~g/L[/tex]
d. CH₄MW=16.04 g/mol
[tex]\tt \rho=0.0446\times 16.04=0.715~g/L[/tex]
e. HFMW=20.01 g/mol
[tex]\tt \rho=0.0446\times 20.01=0.892~g/L[/tex]
what is 1.23 x 10^-3 in standard notation
Answer:
=0.00123
Explanation:
Look at the attachments below
Hope this helps (:
Answer:
0.00123
Explanation:
Standard notation is the normal way of writing numbers. Examples include 1, 2, and 10. The number 1.23 x 10^-3 is written in scientific notation. The decimal goes after the first nonzero integer and it is multiplied by a power of 10. The power or exponent attached to the 10 tells you how many places over you need to move the decimal to get back into scientific notation. Examples include 1.00 x 10^2 (representing 100 in standard form because you would move the decimal two places to the right.), 2.0 x 10^1 (representing 20 in standard form because you would move the decimal one place to the right), and 3.0 x 10^-4 (representing 0.0003 in standard form because you would move the decimal four places to the left since it is a negative exponent).
The negative (-3) exponent in 1.23 x 10^-3 indicated to move the decimal three places to the left. If it was positive, you would move it three places to the right.
In 1.23 x 10^-3 move the decimal to the left 1 place to get:
0.123
two places to get:
0.0123
and a third place to get:
0.00123
The final answer is 0.00123
A penny is 2.5 g. How many kilograms does a penny weigh?
Answer:
The penny now weighs 0.0025kg
Hope this helps please give me brainliest!
God bless!
Based on the article "Will the real atomic model please stand up?," describe what Dalton's theory states about a molecule of water. Dalton's theory about compounds tells us that all water molecules have different kinds of atoms, two hydrogen atoms for every one oxygen atom.
Answer:
Follows are the solution to this question:
Explanation:
The characterization with water molecules would be that light waves are made up of 2 different types of atoms (2 hydrogen and 1 oxygen atoms), as per the Dalton theory. There are many multiple times as many atoms of hydrogen as oxygen atoms in each water molecules. For every two hydrogen atoms, all water molecules have one oxygen atom.
Answer:
Sample Response: Dalton’s theory about compounds tells us that all water molecules have different kinds of atoms, two hydrogen atoms for every one oxygen atom.
Explanation:
6. A sheet of metal is 2 cm wide, 10 cm tall, and 15 cm long. It was 4 grams. What is the
density?
Answer:
0.013g/cm^3
Explanation:
density= mass÷volume
Answer:
0.01(3) g/cm3 (cm3 means centimeter cubed, (3) means the 3 goes on forever)
Explanation:
The volume of the sheet is 300 cm3, and dividing 4 grams by 300 cm3 gets you 0.01(3) g/cm3. Hope it helps!
Where exactly is an orbital? I understand they are a volume where we expect to find electrons 90% of the time but I don't understand where their shapes are and fit on an atom, and the different forms of orbitals confuse me a little. Can someone explain me where they are with the help of an image? Pardon me if my question isn't very clear
Answer:
95% of the time (or any other percentage you choose), the electron will be found within a fairly easily defined region of space quite close to the nucleus. Such a region of space is called an orbital. You can think of an orbital as being the region of space in which the electron lives
how many atoms can you fit on the head of a pin
Answer:
According to google, "About five million million hydrogen atoms could fit. Some factors would affect that number like the area of the head and the size of atoms (as well as attractions between atoms). Some atoms are larger than others." Is this accurate? I'm not sure. Good luck! :)
1. Using a triple beam balance and a graduated cylinder, a student collected data on a sample of an
element:
Mass of sample - 67.9 g
Volume of water - 52.0 ml
Volume of water and sample - 28.0 ml
a) Calculate the density of the sample. Show all work and use significant figures and units.
Answer:
d = 2.8 g/mL
Explanation:
Given data:
Mass of sample = 67.9 g
Volume of water = 28.0 mL
Volume of water + sample = 52.0 mL
Density of sample = ?
Solution;
Density is equal to the mass of substance over volume of substance.
Formula:
d = m/v
d = density
m = mass
v= volume
Now we will calculate the volume of sample.
Volume of sample = (volume of water+ sample) - volume of water
Volume of sample = 52.0 mL - 28.0 mL
Volume of sample = 24.0 mL
Now we will calculate the density.
d =67.9 g /24.0 mL
d = 2.8 g/mL
Convert 122 moles of Methane to liters?
Which of the following is false regarding supersonic speed?
Question 10 options:
When an object reaches supersonic speed a sonic boom will occur.
When an object reaches supersonic speed it is moving faster than the speed of light.
When an object has reaches supersonic speed it breaks the sound barrier.
When an object supersonic speed it is moving faster than 343 meters/second.
Answer:
the answer is C
Explanation:
i know this one, and may YOU PLEASE MARK BRAINLIEST I ONLY NEED ONE MORE CROWN TO MOVE TO THE NEXT RANK
cy sprints 100 meters in 13 seconds going south. what is his average velocity?
Answer:
Explanation:
This should be in physics.
d = 100 meters south
t = 13 seconds
v = d/t
v = 100 / 13
v = 7.69 m/s going south.
The point is that you have to specify the direction.
You will learn in this course that organic compounds have covalent bonds with a significant amount of energy stored in them. This is why we burn fossil fuels to generate energy to heat our homes or drive our cars. Given this information, which of the compounds listed below would you expect to have the most energy is its carbon-carbon bond?
Answer:
See explanation
Explanation:
This question is obviously supposed to be a multiple choice question but the options are missing.
However, the question intends to test the student's knowledge about combustion of fossil fuels. Fossil fuels are mostly composed of hydrocarbons of different chain lengths.
The longer the chain length, the greater the energy released when the compound is burnt since there are more energy stored in its bonds.
Hence, the correct answer to this question will be the option that contains the greatest number of C-C and C-H bonds.
What is the last energy level of N? Mg?
Answer:
2
3
Explanation:
To infer the last energy of the given atoms, we need to write their electronic configuration:
For N = 1S² 2S² 2P³
Mg = 1S² 2S² 2P⁶ 3S²
The energy levels are usually designated as;
n = 1
n = 2
n = 3
n =4
For N, the last energy level is 2
Mg, the last energy level is 3
We can also determine this number by the periods the atoms can be found.
What is the correct name for the compound P406?
A. Phosphoric acid
B. Tetraphosphorus hexoxide
C. Phosphorus (IV) oxide
D. Phosphorus oxide
Answer:
Phosphorus trioxide
Explanation:
Answer:
Tetraphosphorus hexoxide
Explanation:
Give brainliest please
A student observes that instant tea dissolves more rapidly in a cup of 250 mL of stirred hot water than in a cup of 250 mL of stirred cold water. Which is the most relevant hypothesis that the student could develop based on this observation?
A.
Volume affects the rate that instant tea dissolves in a solvent.
B.
Temperature affects the rate that instant tea dissolves in water.
C.
Stirring affects the rate that instant tea dissolves in water.
D.
Pressure affects the rate that instant tea dissolves in water.
Please answer my question!
Answer:
B
Explanation:
In this question, there is no mention of pressure, so we can eliminate answer D. In both cups, it mentions they contain 250 mL of water and both are stirred, so these would be constants. The only difference between the cups is temperature, so temperature must affect the rate that instant tea dissolves in water. Therefore the answer is B.
What questions might remain that will one day be answered by new technology?
Answer:
Can we find a safe cure for cancer?
Explanation:
pls mark brainliest
How would an astronomer identify our home in the universe? Earth is in the solar system. The Milky Way is in the solar system. The solar system is next to the Milky Way. Earth is in the Milky Way and next to the solar system. The Milky Way is in the universe. The solar system is in the Milky Way. Earth is in the solar system. The universe is in the Milky Way. The Earth is in the Milky Way. Earth is at the center of the solar system.
Answer:
Earth is in the solar system.
Explanation:
Earth is our home and it is in the solar system.
Earth is the fifth-largest of the planets in the solar system and the third planet from the sun. Earth is the only planet having oxygen and water that supports life. Till now according to the research Earth is the only planet having life.
Planets are in the solar system, the solar system is in the milky way and the milky way is present in the universe. The astronomer identifies our home in the universe as "Earth is in the solar system" as Earth is our home.
Hence, the correct answer is "Earth is in the solar system."
Answer:
The Milky Way is in the universe. The solar system is in the Milky Way. Earth is in the solar system.
Explanation:
If the Milky Way Is in the universe and solar system you would know earth is also In the solar system, so "Our home planet is the third planet from the Sun, and the only place we know of so far that's inhabited by living things. While Earth is only the fifth largest planet in the solar system, it is the only world in our solar system with liquid water on the surface."
Which helps in the production of eggs?
Answer:
Feed Consistency.
Explanation:
Feeding that is supposed to yield the volume of a gnome for our chickens to lay eggs.
The Boxes of Clean Nests.
The Areas Free.
With calcium.
Regularly check it.
Protection Coop.
About fresh water.
Controlling Parasites.
Answer:
A. testosterone
Explanation:
i took the unit test
Which description applies to a physical property? Choose the correct answer
O depends directly on the amount of the substance present
O examines changes in the composition and structure of matter
O measured or observed without changing the identity and composition of matter
O determined by changing the identity of a substance and observing how it reacts
Answer:
the third one, measured or observed without changing the identity and composition of matter. because physical property does not under go any change but can be put back.
what unit of measure would i use to measure the width of my fingernail A millimeters
B centimeters C meters D kilometers
E grams
Please answer it correctly and explain clearly
Answer:
i think that the children will inherit the brown eyes, it is the best answer since the other things cant be inherited and he dyed his hair blonde
Explanation:
Which further observation led Mendeleev to create the periodic table
Answer:
Mendeleev realized that the physical and chemical properties of elements were related to their atomic mass in a 'periodic' way, and arranged them so that groups of elements with similar properties fell into vertical columns in his table.
Explanation:
Dilute hydrochloric acid reacts with sodium
2HCl(aq) + Na2CO3(aq) + 2NaCl(aq) + H2O(l) + CO2(g)
A Explain why effervescence is seen during the reaction.
Answer:
Because the reaction releases CO2 gas
Explanation:
therefore creating an effervecence within the solution as the carbonate dissociates
How many neutrons make up one of these potassium atoms?
Answer:
20
Explanation:
Plowing is an example of what Energy?
a. Kinetic Energy
b. Potencial Energy
Answer:
mechanical or kinetic eg hammer and nails
What accounts for the attractions in a chemical bond?
Answer:
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds.
Explanation:
Please help!
We are doing a lab and I have trouble doing the data analysis. Using my data collection, Can you guys help me using the MC delta T equation?
4.94 x c . (Tm-23.6)=C.(23-6-21.9)+123.13 x c. (23.6-21.9)
Further explanationThe law of conservation of energy can be applied to heat changes, ie the heat received/absorbed is the same as the heat released
Q in = Q out
Heat can be calculated using the formula:
Q = mc∆T
A calorimeter is a device used to measure the specific heat of material
A metal is put into a calorimeter that contains water and there will be heat transfer:
[tex]\tt \displaystyle m_mc_m (T_m-T)=m_wc_w(T-Tw)[/tex]
m = metal
w = water
T = the final temperature of the mixture
mass of metal =(Nickel) = 4.94 g
mass of calorimeter = 12.5 g
mass of water = 123.13 g (135.63 - 12.5)
The equation
Q released (metal) = Q absorbed(calorimeter+water)
Qmetal = 4.94 x c . (Tm-23.60)Q calorimeter = C.(23-6-21.9) --> C = heat capacity of calorimeterQ water = 123.13 x c. (23.6-21.9)The equation :
4.94 x c . (Tm-23.6)=C.(23-6-21.9)+123.13 x c. (23.6-21.9)