Answer:
80g=0.08kg
20cm=0.02m
density=m/v
= 0.08/0.02
=4kg/m^3
it is less than density of water so it floats
Explain why the available amount of water per person differs between countries.
Answer:
It's considered a limited resource because there is a limited amount of freshwater found on Earth's surface. Explain why the amount of water per person differs between countries. It differs because in the different countries it is distributed unevenly.
Explanation:
looked it up
Which celestial object's period of revolution is the same as its period of
rotation?
Answer:
MOON
Explanation:
ITS PERIOD OF REVOLUTION IS EQUAL TO PERIOD OF ROTATION
please hit the heart button
If ice has a density of 0.92 g/ml what is the volume of 5,000g of ice?
Answer:
The answer is 5,434.8 cm^3
The volume corresponding to 5,000 g of ice with a density of 0.92 g/mL is 5.4 × 10³ mL.
The density (ρ) is an intrinsic property of matter. It is equal to the quotient between the mass (m) and the volume (V). If we have 5,000 g of ice with a density of 0.92 g/mL, its volume is:
[tex]\rho = m/V\\V = m/\rho = 5,000 g/(0.92 g/mL) = 5.4 \times 10^{3} mL[/tex]
The volume corresponding to 5,000 g of ice with a density of 0.92 g/mL is 5.4 × 10³ mL.
You can learn more about density here: https://brainly.com/question/21667661
I need help fast...........
Answer:
I think its might be 1 because the ionic numbers for CA is +2 and for P its +3
How many grams do 3.6 × 10^20 atoms of sodium weigh?
Answer in units of g.
Second time posting as someone else answered incorrectly.
Answer:
13.749 x 10 -3 g
Explanation:
take the number of atoms that you have divided by Avogadro's number and then multiply by the molar mass of the element. :)
Calculate the atomic mass of Copper if copper-63 is 69.17% abundant and Copper-65 is 30.83% abundant.
The atomic mass of Copper : 63.6166 amu
Further explanationGiven
Copper-63 is 69.17%
Copper-65 is 30.83%
Required
The atomic mass of Copper
Solution
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% ...
The atomic mass of Copper = 0.6917 x 63 + 0.3083 x 65
The atomic mass of Copper = 43.5771 + 20.0395
The atomic mass of Copper = 63.6166 amu
How are you able to see cells?
With contemporary light microscopes.
Answer:
Contemporary light microscopes are able to magnify objects up to about a thousand times. Since most cells are between 1 and 100 μm in diameter, they can be observed by light microscopy, as can some of the larger subcellular organelles, such as nuclei, chloroplasts, and mitochondria.
What kinds of shapes can carbon based molecules form?
Answer:
Straight chains, branched chain and rings.
Explanation:
Hope this helps :)
Answer/Explanation:
Carbon based molecules tend to form in chain like patterns. So, carbon molecules could/would form a chain that branches out, a chain that travels in a straight or constant direction, and a chain that connects into a loop style.
1.Explain why the reactivity of group 7 decreases as you move down the group. Try to use the sentence starters here: When group 7 elements react, their atoms….
As you move down the group, the outer shells get…
Therefore the force of attraction between the shells and the nucleus is….
This makes attracting an extra electron…
Consequently, reactivity…
Answer: The reactivity of group 7 decreases as we move down the group because:
Explanation:
The elements of group 7 that is fluorine to iodine. The halogens are non metals and they react with metals to gain electrons. The metals loose electrons and the non metal gains it.
As we move down the group the atomic radius gets bigger( more electron and more proton) and as a result the outer shells move further away from the nucleus.
There is more distance between the negatively charged electrons and positively charged nucleus.
Therefore the force of attraction between the shells and nucleus is lesser or weaker.
This makes attracting an extra electron from metals very difficult which results in weaker reaction.
Consequently, the reactivity decreases as we move down the group 7
What is the pH of a solution with (H+] = 1 x 103 M?
Multiple Choice
Over time, a particular plant has developed a longer stamen. Which of the following is a possible advantage of having a longer stamen?
A. A longer stamen could ensure that an insect brushes against an anther and picks up pollen.
B. A longer stamen could ensure that the flower produces more nectar.
C. A longer stamen could ensure that pollen could reach the ovary and fertilize the egg.
D. A longer stamen could ensure that the developing flower is well protected.
Answer:
A) A longer stamen could ensure that an insect brushes against an anther and picks up pollen.
Explanation:
The stamen will provide easier access to the pollen.
Hope this helps :)
a) Find the gas speed of ammonia at 25.0 degrees Celsius. ______________
b) What is the rate of effusion of ammonia compared to silicon tetra bromide gas as the same temperature? __________________
a. 661.23 m/s
b. the rate of effusion of Ammonia = 4.5 faster than Silicon tetra bromide
Further explanationGiven
T = 25 + 273 = 298 K
Required
a. the gas speed
b. The rate of effusion comparison
Solution
a.
Average velocities of gases can be expressed as root-mean-square averages. (V rms)
[tex]\large {\boxed {\bold {v_ {rms} = \sqrt {\dfrac {3RT} {Mm}}}}[/tex]
R = gas constant, T = temperature, Mm = molar mass of the gas particles
From the question
R = 8,314 J / mol K
T = temperature
Mm = molar mass, kg / mol
Molar mass of Ammonia = 17 g/mol = 0.017 kg/mol
[tex]\tt v=\sqrt{\dfrac{3\times 8.314\times 298}{0.017} }=661.23~m/s[/tex]
b. the effusion rates of two gases = the square root of the inverse of their molar masses:
[tex]\rm \dfrac{r_1}{r_2}=\sqrt{\dfrac{M_2}{M_1} }[/tex]
M₁ = molar mass Ammonia NH₃= 17
M₂ = molar mass Silicon tetra bromide SiBr₄= 348
[tex]\rm \dfrac{r_1}{r_2}=\sqrt{\dfrac{348}{17} }=4.5[/tex]
the rate of effusion of Ammonia = 4.5 faster than Silicon tetra bromide
What is the relationship between distance from the Sun and period of
revolution for the planets in our Solar System?
Answer:
T^2 α r^3
Explanation:
The relationship between the period of revolution of planets and their mean distances from the sun is given by Kepler's third law.
Kepler's laws of planetary motion describe the orbits of objects around the sun.
This third law states that; "the square of the period of revolution of planets are proportional to the cubes of their mean distances from the sun. Hence; T^2 α r^3.
Where;
T = period of revolution of the planets
r = mean distance of the planet from the sun
Are electrons exchanged between ionic or covalent bonds
Answer:
Ionic bonds form when a nonmetal and a metal exchange electrons, while covalent bonds form when electrons are shared between two nonmetals.
Help please!!
The half life of lutetium-117 is 6.75 days.
Calculate the percentage remaining after 27 days.
Answer:
6.25%
Explanation:
Given data:
Half life of lutetium-117 = 6.75 days
Percentage remaining after 27 days = ?
Solution;
Number of half lives = Time elapsed / half life
Number of half lives = 27 days / 6.75 days
Number of half lives = 4
At time zero = 100%
At first half life = 100%/2 = 50%
At second half life = 50%/2 = 25%
At 3rd half life = 25%/2 = 12.5%
At 4th half life = 12.5%/2 = 6.25%
plssss help me I only have 10 mins.
Answer:
Scientists must collect accurate information that allows them to make evolutionary connections among organisms. Similar to detective work, scientists must use evidence to uncover the facts. In the case of phylogeny, evolutionary investigations focus on two types of evidence: morphologic (form and function) and genetic.
Explanation:
This what I think
Answer:
C
Explanation:
Just like a Alligator or Croc, they evolved from the dinosuar's. The scientest KNOW THIs mainly because they have compared the fossil's of a crocidile THEN and a corcidile NOW (Just a example)
Hope this helps and pls mark brainlest!
The first order reaction,so2cl2 to so2+cl2,has a half life of 8.75 hours at 593k.How long will it take for the concentration of so2cl2 to fall to 12.5% of its initial value? 6.24hours 26.2hours 16.2hours 22.6hours
Answer: The time after which the concentration of [tex]SO_2Cl_2[/tex] fall to 12.5% of its initial value is 26.2 hours
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = 100
a - x = amount left after decay process = 12.5
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{8.75hour}=0.0792hour^{-1}[/tex]
b) for concentration to fall to 12.5 % of initial value
[tex]t=\frac{2.303}{0.0792}\log\frac{100}{12.5}[/tex]
[tex]t=26.2hours[/tex]
The time after which the concentration of [tex]SO_2Cl_2[/tex] fall to 12.5% of its initial value is 26.2 hours
In your opinion, should scientists clone the wooly mammoth? Explain why or why not.
Answer:
I think scientists should not clone the wooly mammoth because our environment is already working great without them and bringing them back has a chance to hurt the environment or even destroy it also wooly mammoths were exists about 3700 years ago and the world had changed A LOT from then so we could end up hurting the mammoth by putting it in a world that has changed a lot from when the wooly mammoth was actually alive.
Which solution would have the highest boiling point? A. 1.3 m ammonium sulfide (aq) B. 2.0 carbon tetrachloride (aq) C. 1.5 m copper (II) sulfate(aq) D.2.2 m sucrose (aq)
Answer:
C. 1.5 m copper(II) sulfate(aq)
Explanation:
I say this because a copper is a metal and a metal always has the highest melting and boiling point. A metal is also malleable, can dissolve in water, and a good conductor of electricity. All the other answers have all the nonmetals in them like Carbon, Oxygen, Chlorine, and etc. Nonmetals do not have a high boiling point. They basically are brittle. Therefore, the final answer is C.
can anyone help please ?
Answer:
The mass remains constant
Explanation:
Burning a wood is a chemical change which produces many products. According to the law of conservation of mass, matter is neither created nor destroyed in a chemical reaction.
This implies that the quantity of the product and reactants will remain the same before and after the reaction. When we write a balanced reaction equation for this process, we find that the number of moles are conserved and the same. So, this is replicated in the mass of the combining species and the product they form. For such a combination, mass is the same.50 points please help
Answer:
The answer is 20mph
Hope this helps!!!
This question was posted more than a month ago so... I guess I'll take the points if you don't mind?
Where does the energy of a nuclear power plant come from?
A) the radiation released by unstable uranium isotopes
B) the heat energy released during nuclear fusion
C) the radiation released when hydrogen fuses into helium
D) the heat energy released during nuclear fission
Answer:
The heat energy released during nuclear fusion
The heat energy released during nuclear fusion. The correct option is D.
Thus, The Sun and other stars are powered by nuclear fusion reactions. A heavier nucleus is created when two light nuclei fuse together in a fusion reaction.
Because the mass of the resulting single nucleus is smaller than the combined mass of the two initial nuclei, the process produces energy. Remaining mass is converted to energy.
Why this happens is explained by Einstein's equation (E=mc2), which states in part that mass and energy can be transformed into one another. Fusion energy could be a significant source of energy generation if scientists can figure out how to use it in equipment on Earth.
Thus, The heat energy released during nuclear fusion. The correct option is D.
Learn more about Nuclear fusion, refer to the link:
https://brainly.com/question/33558814
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In the equation shown, what are the reactant(s)?
CsHot 0,7H2O+CO2
C=1
H = 8 H=2
0 = 2
C=3
O=3
wie
O C3H8
Most chemical reactions release energy or are exothermic. However, some reactions, such as some decompositions, absorb energy. These reactions can be best explained by which of these? A) Energy is destroyed in the chemical reaction. B) The products have less energy stored in their chemical bonds. C) The products have more energy stored in their chemical bonds. D) The reactants have the same energy stored in their chemical bonds.
Answer:
C) The products have more energy stored in their chemical bonds.
Explanation:
In such reactions that absorb energy, the products have more energy stored in their chemical bonds.
For endothermic changes, heat is absorbed from the surrounding hence the surrounding becomes colder at the end of the changes.
The heat energy level of the products is higher than that of the reactants.
Exothermic reactions releases heat to the surroundings. The sum of heat contents of the products is less than that of the hat contents of the reactants. Examples of such processes are burning and dissolution.A student places a small stone with a mass of 5 g into a graduated cylinder containing 50 mL of water. With the stone in the graduated cylinder, the water rises to 75 mL. What is the density of the stone? a. 0.07 g/mL b. 0.20 g/mL c. 5.00 g/mL d. 125.00 g/mL
Answer:
0.20 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
volume = final volume of water - initial volume of water
volume = 75 - 50 = 25 mL
From the question we have
[tex]density = \frac{5}{25} = \frac{1}{5} = 0.2 \\ [/tex]
We have the final answer as
0.20 g/mLHope this helps you
which statement describes the movement of carbon dioxide in the carbon cycle?
A. The gas leaves the biosphere as animals breathe in air.
B. The gas leaves the atmosphere as plants use it to make sugar.
C. The gas enters the cryosphere as ice sheets melt.
D. The gas enters the hydrosphere as sugar dissolves in water.
Answer:
C. The gas enters the cryosphere as ice sheets
Answer:
D
Explanation:
How do covalent bonds form neutral compounds?
Answer:
Covalent bonds form when electrons are shared between atoms and are attracted by the nuclei of both atoms.
How many grams of zinc oxide can be produced from 7.3 moles of oxygen? *
2Zn + O2 → 2Zno
1188.13 g Zno
81.379 g Zno
7.3 g Zno
O 2g Zno
Answer:
Mass = 1188.13 g
Explanation:
Given data:
Mass of ZnO produced = ?
Moles of oxygen = 7.3 mol
Solution:
Chemical equation:
2Zn + O₂ → 2ZnO
Now we will compare the moles oxygen and and ZnO.
O₂ ; ZnO
1 : 2
7.3 : 2/1×7.3 = 14.6 mol
Mass of ZnO:
Mass = number of moles × molar mass
Mass = 14.6 mol × 81.38 g/mol
Mass = 1188.13 g
Describe what happens to particles of matter as you cool the matter to absolute zero (0 K). In your description, be sure to explain the changes in kinetic energy and particle motion.
Answer:
the particles expand and the kinetic energy i think moves slower
Explanation:
Answer:
Absolute zero is the temperature at which the particles of matter (molecules and atoms) are at their lowest energy points. Some people think that at absolute zero particles lose all energy and stop moving. This is not correct. ... Scientists use lasers to slow atoms when cooling objects to very low temperatures.
What is the main function of the circulatory system?
A.
to eliminate waste from the body
B.
to distribute blood and nutrients throughout the body
C.
to support the body and allow movement
D.
to protect the body from infectious agents