Answer:
Explanation:
Kinetic energy is the energy due to changes in position of a body. It is always with regards to motion of a body.
Potential energy on the other hand is the energy at rest of a body.
To estimate kinetic energy, we use the formula:
K.E = [tex]\frac{1}{2}m v^{2}[/tex]
where m is the mass of the body and v is the velocity of the object.
mass is 5kg and velocity is 5ms⁻¹
K.E = [tex]\frac{1}{2}5 x 5^{2}[/tex]
K.E = 62.5J
for the object at rest;
potential energy is calculated:
P.E = mgh
where m is the mass, g is the acceleration due to gravity and h is the height
m is 5kg, h is 2 and g is 9.8
P.E = 5 x 9.8 x 2 = 98J
The moving object has kinetic energy with the object at rest having potential energy.
The moving object has kinetic energy with the object at rest having potential energy.
How many kg are in 10 pounds
Answer:4.536 kilograms
Explanation:
for an approximate result, divide the mass value by 2.205
eview Questions
1. Compare qualitative and quantitative physical properties. Use
examples of properties listed in Tables 4.2 and 4.3 as part of your
discussion
Answer:
Qualitative: Physical observations (the sky is blue, the water is boiling, etc.)
Quantitative: Numberical observations (density= 1 g/ml, volume= 14 ft^3, etc.)
Explanation:
The way to remember it is quaLitative is qualities of the object. QuaNtitative is quantities of the object.
Qualitative physical properties describe the quality of matter without numbers, such as color, while quantitative properties involve numbers and units, like a substance's melting point.
Qualitative and quantitative physical properties differ in the way they describe matter. Qualitative physical properties describe the quality of a substance without using numbers. For example, sulfur being yellow is a qualitative description. On the other hand, quantitative physical properties specify the quantity and include numerical values with units, such as a book having 650 pages.
To illustrate these differences, consider the physical property of color. Color is a qualitative property because it describes what we see without measurement. In contrast, melting point is a quantitative property because it provides a specific temperature at which a substance changes from a solid to a liquid, such as ice melting at 0°C.
Use the periodic table to match each of the following element symbols to its name, atomic mass, or atomic number
Match
B) 78.971 u (atomic mass)
c) 16 (atomic number)
The matching of each of the following element symbols to its name, atomic mass, or atomic number can be done as;
Tin ; symbol(Sn) atomic number (50)., atomic mass of (118.710 )Selenium; Symbol( Se) Atomic Number (34) (Atomic Mass 78.96 atomic mass units)Sulfur ; symbol (S) ,atomic number (16). How can the matching be done?Sulfur is a chemical element with the atomic number 16 and the symbol S. Sulfur is a solid at ambient temperature and is categorized as a nonmetal.
Tin is a Group 14 (the carbon family) element with mostly metallic characteristics. Tin has an atomic mass of 118.710 atomic mass units and an atomic number of 50.
Tin is the element listed as Sn in the periodic table. Stanum is the latin name of the metal from which Sn is derived.
Se is a group 6 element and is selenium. It is a member of the same group as tellurium, oxygen, and sulfur. The atomic weight of this material is 78.96 g/mol.
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An atom of the element zinc has an atomic number of 30 and a mass number of 65. How many protons does an uncharged
zinc atom have?
Answer:
30 The atomic number is the number of protons
Explanation:
Answer:
An uncharged zinc atom have 30 protons.
Explanation:
Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z. But in the nucleus of each element it is also possible to find neutrons, the number of which can vary. The atomic mass (A) is obtained by adding the number of protons and neutrons of a given nucleus.
In this case, an atom of the element zinc has an atomic number of 30 and a mass number of 65. So, you can know that Z=30 and A=65. Then, the number of protons is 30. And knowing that the number of protons plus the number of neutrons is 65, it is possible to say that the number of neutrons is 35.
Finally, an uncharged zinc atom have 30 protons.
Cecil is working with samples of chlorine (CI), oxygen (O), bromine (Br), and silver (Ag). The samples are all at room
temperature. Which substance is most likely the most dense?
chlorine
oxygen
bromine
silver
Answer:
silver
Explanation:
Silver is a metal at room temperature.
The physical state of matter can help us know which of these substances will be the most dense. Density deals the amount of substances per unit volume.
Solids are packed closely and have a definite and ordered arrangement of their atoms. From the list above only Silver is a solid at room temperature.
Bromine is a liquid at room temperature while chlorine and oxygen are gases at room temperature. Liquids and gases do not have more substances per unit volume compared to solids. Therefore, silver should be the most dense.
Answer:
The answer is silver. Silver is the most dense, it's a solid so it is more compact and is obviously the most likely to have more mass to it. option D
Explanation:
On average, water flows over a particular water fall at a rate of 2.02 x 105 cubic feet per second. One cubic foot of water weighs
62.4 lb. Calculate the rate of water flow in tons of water per day. (1 ton = 2200 lb)
2.40e15
tons/day
the tolerance is +/-2%
Answer:
Approximately 5.00 × 10⁸ tons per day. (Rounding error: less than 1.1%.)
Explanation:
How many cubic feet of water flows over this waterfall each day?
The question gives only the number of cubic feet of water that flows over each second. To find the volume for each day, start by finding the number of seconds in a day.
There are 60 seconds in a minute and 60 minutes in an hour. That translates to [tex]60 \times 60[/tex] seconds in an hour.
There are 24 hours in a day. Each hour contains [tex]60 \times 60[/tex] seconds. That means that there are [tex]24 \times 60 \times 60[/tex] seconds in a day.
[tex]2.02 \times 10^{5}[/tex] cubic feet of water flows over this waterfall every second. Therefore, [tex]24 \times 60 \times 60\times 2.02 \times 10^{5}[/tex] cubic feet of water flows over this waterfall every day.
The weight of one cubic foot of water is [tex]62.4[/tex] pounds. The weight of [tex]24 \times 60 \times 60\times 2.02 \times 10^{5}[/tex] of cubic feet of water will be [tex]24 \times 60 \times 60\times 2.02 \times 10^{5}\times 62.4[/tex] pounds.
It takes 2,200 pounds to make a ton. [tex]24 \times 60 \times 60\times 2.02 \times 10^{5}\times 62.4[/tex] will translate to [tex]\displaystyle \frac{1}{2200}\times 24 \times 60 \times 60\times 2.02 \times 10^{5}\times 62.4[/tex] tons.
To calculate the rounding error, evaluate
[tex]\displaystyle \frac{\text{Rounded Value} - \text{Actual Value}}{\text{Actual Value}}\times 100\%[/tex] and drop the negative sign if there is one. Rounding the final result to [tex]5.00\times 10^{5}[/tex] gives a rounding error of approximately [tex]1.0\%[/tex].
Water flowing over a particular waterfall at a rate of 2.02 x 10⁵ ft³/s is equivalent to 4.95 × 10⁸ ton/day.
First, we will convert 2.02 x 10⁵ ft³/s to ton/s using the following conversion factors:
1 ft³ of water = 62.4 lb of water (this refers to the density of water).1 ton = 2200 lb[tex]\frac{2.02 \times 10^{5} ft^{3} }{s} \times \frac{62.4lb}{1ft^{3} } \times \frac{1ton}{2200lb} = 5.73 \times 10^{3} ton/s[/tex]
Then, we will convert 5.73 × 10³ ton/s to ton/day using the following conversion factors:
1 h = 3600 s1 day = 24 h[tex]\frac{ 5.73 \times 10^{3} ton}{s} \times \frac{3600s}{1h} \times \frac{24h}{1day} = 4.95 \times 10^{8} ton/day[/tex]
Water flowing over a particular waterfall at a rate of 2.02 x 10⁵ ft³/s is equivalent to 4.95 × 10⁸ ton/day.
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Describe the results of a physical change and list
three examples of physical change.
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.
Ex: cutting a paper, gaining weight, cutting hair
Physical changes end result handiest in a trade in the shape (i.e., strong, liquid, gasoline) or look of a substance, however no longer the chemical composition of the substance.
The substance will still in the end be the same. as soon as a bodily change occurs, it could be reversed.
What are the examples of physical changes?Modifications within the length or form depending are examples of bodily trade. Physical changes consist of transitions from one country to another, together with from stable to liquid or liquid to gasoline. cutting, bending, dissolving, freezing, boiling, and melting are some of the tactics that create bodily changes.
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26.42m Significant figure
Answer:
4 sig figs
Explanation:
There are 4 because they are all # 1 or above.
0 has special rules on whether or not it is significant.
0 being between two other sig figs no matter how far apart makes it a sig fig.
example: 101 is 3 sig figs
0 that is at the end of a non decimal number are not significant.
example: 110 is 2 sig figs
0 that are after a decimal are significant as long as they after another sig fig.
example: 1.000 and .1000 are both 4 sig figs
extra examples:
110.01 is 5 sig figs
110.1 is 4 sig figs
.0001 is 1 sig figs
Is this how you draw a punnet square???
Answer:
No
Explanation:
Two letters on the top, and two letters on the left. (one letter per square)
Answer:
No, it is not.
Explanation:
To draw a Punnett Square, it can only have 4 letters on 2 sides.
I added an image which is an example.
How many milliliter are in 0.063 L
Answer:
63 mL
Explanation:
To find the amount of mililiters in an amount of liters, we must multiply by the amount of liters by 1000.
0.063 L × 1000 = 63 mL
Which statement is true about this reaction?
14N+H—>150
A-It is a practical source of energy on Earth.
B-It occurs only outside the solar system.
C-Its product is heavier than each of its reactants.
D-It shows the critical mass of an element
Answer:
C-Its product is heavier than each of its reactants.
Explanation:
Correct equation:
¹⁴₇N + ¹₁H → ¹⁵₈O
In the reaction above, we can conclude within the given conditions of the reaction that the product formed is heavier than the reactants.
The product is oxygen with a mass number of 15 as shown by the superscript preceeding the symbol of the atom.
The reactants are:
Nitrogen, N with a mass number of 14
Hydrogen, H with a mass number of 1
The mass number is a true reflection of the mass of an atom. It clearly shows the mass of the nucleons which are the most massive particles that makes up an atom. The nucleons are protons and neutrons that makes up the tiny nucleus of the atom.
Oxygen here has more nucleons that each of Nitrogen and Hydrogen.
Answer:
c
Explanation:
Archeologist discovered a silver crown in an ancient tomb and sent it for analysis. You placed the crown in a tub of water and found it displaces 238.1 ml of water. If the mass of the crown is 2.50kg did the archeologist find a crown of Real silver? How can u be sure?
Answer:
Explanation:
The density of pure lead is 10.49g/cm³
Given parameters:
Volume of water displaced by the crown = 238.1ml
Mass of crown = 2.50kg
Solution
We would simply find the density of the discovered crown and compare with that of the standardized density of lead.
Density is an intensive property of matter and it is the same for any form of matter. It is amount of substance per unit volume:
Density = [tex]\frac{mass}{volume}[/tex]
We need to convert the given parameters to standard unit,
1ml = 1cm³
Therefore, the volume of water displaced is 238.1cm³
Also,
1kg = 1000g
2.5kg = 2500g
mass of the crown is 2500g
Density = [tex]\frac{2500}{238.1}[/tex] = 10.49g/cm³
The crown is made of silver because the density matches with that of pure silver.
how many electrons are in 1.39e23 atoms of carbon 13?
Answer:
8.34e23 electrons
Explanation:
One atom o 13C has 6 electrons, 6 protons, and 7 neutrons
so 1.39e23 13C atoms will have 1.39e23 x 6 = 8.34e23
Each Carbon-13 atom has exactly 6 electrons. So, 1.39e23 atoms of Carbon-13 would contain a total of 8.34e23 electrons.
Explanation:To figure out the number of electrons in 1.39e23 atoms of Carbon-13, you need to understand that each atom of carbon-13 contains exactly 6 electrons (as its atomic number is 6). The total number of electrons is simply the number of atoms multiplied by the number of electrons per atom. Hence, the total number of electrons is 1.39e23 * 6 = 8.34e23 electrons.
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the unit of measurement mL describes what property of a substance
Answer:
c) volume
Explanation:
mL is a unit of volume
What is the name of the compound CoS
Answer:
Cobalt sulfide
Explanation:
Cobalt sulfide
The name of the compound CoS is Cobalt Sulfide. It consists of one atom of Cobalt (Co) and one atom of Sulfur (S). The name follows standard chemical naming conventions.
Explanation:The compound CoS refers to a molecule composed of one atom of cobalt (Co) and one atom of sulfur (S). In the naming conventions of chemical compounds, the first element usually retains its standard name, while the second element has its ending changed to '-ide'. Thus, the name of the compound CoS would be 'cobalt sulfide.' It's important to note here that the prefix 'mono-' that is used to denote single atoms is usually omitted, hence we don't say 'monocobalt monosulfide'. To ensure the correctness of the names, strict rules are followed in Chemistry to avoid ambiguity.
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From the following list of elements, those that will always form ionic compounds in a 1:2 ratio with zinc.
Choose one or more:
O A. iodine
O B. nitrogen
O C. fluorine
OD.rubidium
O E, selenium
OF. bromine
O G. sodium
O H zirconium
OI manganese
Answer:
A. iodine
C. fluorine
F. bromine
Explanation:
Ionic bonds occur mostly between metals and non-metals. Usually, a wide electronegativity difference is preferred between the two atoms. This makes one atom more desirous to gain electron and other more willing to donate electrons.
To have Zn forming a compound in the ratio of 1 to 2, the combining power must be similar to this.
The dominant oxidation state of Zn is the is the +2 state.
The other combining atoms must have the ability to recieve the two electrons.
The halogens fit perfectly into this picture. They need just an electron to attain nobility. They are also highly electronegative. If two halogens combines with the Zn, then the ionic bond will result.
The halogens are fluorine,chlorine, bromine, iodine and astatine.
They will form these compounds:
ZnF₂, ZnBr₂ and ZnI₂
Final answer:
Iodine, fluorine, selenium, and bromine can form ionic compounds in a 1:2 ratio with zinc since zinc typically exhibits a 2+ charge and these non-metals form -1 anions.
Explanation:
The question asks which elements from a provided list will always form ionic compounds in a 1:2 ratio with zinc. Zinc, being a transition metal, commonly exhibits a 2+ charge in its compounds. For an ionic compound to form with zinc in a 1:2 ratio, the other element must form an anion with a 1- charge to balance the overall charge of the compound, as zinc donates two electrons (one for each anion). From the given options, the elements that will form anions with a 1- charge and hence can form ionic compounds in a 1:2 ratio with zinc (Zn) are: A. iodine (I), C. fluorine (F), E. selenium (Se), and F. bromine (Br). These non-metals typically form -1 anions, which matches the requirement for forming a 1:2 ratio compound with Zn2+. Therefore, the correct options are A. iodine, C. fluorine, E. selenium, and F. bromine.
Suppose you have a scientific question you are interested in answering. What would you normally do before you make your hypothesis? A. Do some background research. B. Conduct a scientific experiment. C. Make predictions about your question. D. Design a procedure for your experiment.
Answer:
A. Do some background research
There are 5 steps for the scientific method while doing an experiment
Step 1: make a question
Step 2: research that question
Step 3: Hypothesis
Step 4: Test and collect data
Step 5: Conclusion
Answer:
aaaaaaaaaa
Explanation:
Which of the following has the longest wavelength?
A.violet
B.ultraviolet radiation
C.red
D.infrared radiation
Answer:
Infrared radiation
Explanation:
The elecromagnetic spectrum is a group of waves that results from electromagnetic vibrations.
In the spectrum, the frequency of the waves increases as their wavelengths decreases. The spectrum is shown below:
Radio waves Microwaves Infrared Visible light Ultraviolet Xrays
Answer:
agree
Explanation:
ANSWER FIRST GET BRAINLY
This table shows situations that are affecting the Earth’s energy balance in certain areas.
Which situations would result in an increase in the Earth’s surface temperature in that area? Check all that apply.
A.1
B.2
C.3
D.4
E.5
Answer:
1 and 5 I'm pretty sure sorry if i'm wrong the rest look like it wouldn't make sense to me
Explanation:
Answer:
Hey! It's 1 and 5!
Explanation:
Are the changes from a to b and from b to c physical or chemical changes?
explain your answer
A = ice
B = water
C = steam
Answer:
They are physical changes.
Explanation:
This is because there in no chemical reaction taking place, just a physical change.
A physical change in a change in which the chemical structure of the substance does not change. Ice, water and steam are all the same on a molecular level, thus changing from ice to water or from water to steam are physical changes.
A chemical change is a change in which the chemical structure of the substance undergoes a change, since this does not happen going for A to B or B to C they are not chemical changes.
Can magnetism be used to identify a substance
Answer:
yes, ex: iron cobalt and nickel and elements like this are attracted to magnetism
Explanation:
13. True or False: "Converting one form of energy into another form
always involves a loss of useable energy.
Plz help
the experiment where the factors being tested are not applied. It allows scientists to set a baseline to compare the experimental groups that do have factors applied to them.
Test variable (independent variable):
Outcome variable (dependent variable):
Control group:
Answer:
An experiment is a research method performed within a completely controlled environment that uses groups of individuals ( subjects), one of which the factors being tested are not spplied on, an independent factor of the hypothesys ( to be tested ), for example the resilience of a group of teenagers) and a dependant factor that is applied to check how it varyes depending on the tested factor ( for example, the most challanging experience of their generation)
Which physical properties do all stars have? Check all that apply. They are made of gases? They shine very bright? They have a spherical shape? They contain iron in their cores? They make energy through fusion? @nattyames snap
Answer:
All of the above
Explanation:
A star is a hot, giant, massive body that is located millions of miles away. These stars appears to be shiny because of its high temperature that glows producing light. They are comprised of gases such as hydrogen and helium, and they release a huge amount of energy when two hydrogen atoms undergoes fusion.
They generally look star shaped (circular type) from earth but they are somewhat spherical in shape due to their gravity that forces them to get bulge at its equator during its rotation around its own axis.
They have a core that contains iron in them and they progressively formed after the exhaustion of the hydrogen and helium fuel.
Hence, all the given options are correct.
Answer:
The answer is A, C, E for E2020 users. I just took the unit test review.
Explanation:
What is a Boitic factor
Answer:
Biotic components, or biotic factors, can be described as any living component that affects another organism or shapes the ecosystem. This includes both animals that consume other organisms within their ecosystem, and the organism that is being consumed
Explanation:
also you spelt it wrong
calculate the % of calcium carbonate in a mixture of calcium carbonate, sodium carbonate and magnesium sulfate if we obtained 1.73g of calcium carbonate and 2.34g of sodium carbonate and 1.93g of magnesium sulfate
Answer:
Explanation:
Given parameters:
Mass of calcium carbonate = 1.73g
Mass of sodium carbonate = 2.34g
Mass of magnesium sulfate = 1.93g
Unknown:
Percentage of calcium carbonate in the mixture
Solution:
The mixture consists of :
calcium carbonate + sodium carbonate + magnesium sulfate:
To find the percentage of calcium carbonate, we must first find the mass of the mixture by summing the masses of the different compounds that makes up the mixture:
Mass of the mixture = 1.73 + 2.34 + 1.93 = 6.00g
Therefore,
percentage of calcium carbonate = [tex]\frac{mass of calcium carbonate}{mass of mixture}[/tex] x 100
Percentage of calcium carbonate = [tex]\frac{1.73}{6}[/tex] x 100 = 28.83%
28.83 % of calcium carbonate is present.
Calcium carbonate [tex]\rm (CaCO_{3})[/tex] is the compound found in aragonite and calcite and is the major element of shells and skeletons. It is also used as a dietary supplement.
How to calculate the percentage?Given,
Mass of calcium carbonate = 1.73 gMass of magnesium sulfate = 1.93 gMass of sodium carbonate = 2.34 gThe total mass of the mixture will be:
[tex]\begin{aligned}\rm Mass \;of \;mixture} &= \rm \;mass\; of \;CaCO_{3} + \rm \;mass \;of \;NaCO_{3} + \rm \;mass \;of\; MgSO_{4}\\\\&= 1.73 \rm \;g + 2.34 \rm \;g + 1.93 \rm \;g \\\\&= 6.00 \rm \;g \end{aligned}[/tex]
The percentage of a compound or an element in a mixture can be calculated as:
[tex]\% \text{of substance} = (\dfrac{\text{mass of substance} }{\text{mass of mixture}}) \times 100[/tex]
Now substitute values in the formula:
[tex]\begin{aligned}\% \text{of substance} &= (\dfrac{\text{1.73 g} }{\text{6.00 g}}) \times 100\\\\&= 28.8 \%\end{aligned}[/tex]
Therefore, 28.83 % of calcium carbonate is present.
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if you walk 2km from your house to a store then back home, what is your displacement
Answer:
If you walk 2km from your kouse to a store then back nome your displacement is 0km.
Explanation:
Displacement is defined as the distance from your original location. The displacement of the question is 0 because even though you left your house, you came back you your original position. Therefore you are 0km from your original position and have a displacement of 0km.
Your displacement in this case is Zero
How to find the displacementYour displacement is the shortest straight-line distance from your initial position to your final position, regardless of the path you took. In this case, you walked 2 km from your house to the store and then walked 2 km back home.
Since you ended up back at your starting point, your final position is the same as your initial position.
Therefore, your displacement is 0 km. Displacement takes into account only the change in position, not the path taken, and since you ended up where you started, there is no net change in position, resulting in a displacement of 0 km.
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Which of the following is not used to hold liquids?
a.
flask
b.
graduated cylinder
c.
balance
d.
test tube
Please select the best answer from the choices provided
A
B
C
D
Among the given options, balance is an object which is not utilized in order to hold liquids. Thus, the correct option for this question is C.
What are the characteristic properties of liquids?The characteristic properties of liquids are as follows:
Liquid has a definite volume but does not possess a fixed shape. Liquids can be compressed with the help of large pressure.This state of matter has less density as compared to solids.The intermolecular forces of attraction are weaker as compared to solids.They possess considerable space between particles.Objects like flasks, graduated cylinders, and test tubes hold liquid on the basis of their intensity. While balance is an instrument that is used to measure the weight or mass of compounds or substances which is present in solid forms.
Therefore, balance is an object which is not utilized in order to hold liquids. Thus, the correct option for this question is C.
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The distance from Santa Maria to Los Alamos is 16.25 mi. what is the distance in meters?
I need to solve this using dimensional analysis. My conversion factors are: 0.621 mi=1.00 km and 1 km = 1000 m
please help!
Answer:
26,167.47m
Explanation:
Problem:
We are to solve this problem using dimensional analysis:
from the given conversion factors-
0.621mi = 1.00km
1km = 1000m
From the problem, we are groing from miles to metres:
16.25mi x [tex]\frac{1km}{0.621mi}[/tex] x [tex]\frac{1000m}{1km}[/tex]
The mi will cancel out and also the km. This leaves us with the desired unit we want which is meters, m.
= 26,167.47m
Solve using proper scientific notation: (use a ^ for the exponent) (1.26 x 104 kg) + (2.5 x 106 g) = ____________________ in kg ?
Answer:
3.9602 x 10^2
Explanation:
You would first multiply the two together, making sure to put it in correctly on your calculator. Then that would lead you to " 396.04".
Since scientific notation must be between 1-10 you would move the decimal two spots to the left to make it smaller, then keeping in mind that to get it back where it was you must multiply the 10 by a positive two to bring it back a positive two spots.
After converting to the same units, the sum of 1.26 x 10⁴ kg and 2.5 x 10⁶ g (converted to 2.5 x 10³ kg) is 1.51 x 10⁴ kg, when added using proper scientific notation.
To solve the given problem in scientific notation, we first need to convert all units to kilograms. We are given 1.26 x 10⁴ kg and 2.5 x 10⁶ g. Remember that there are 1000 grams in 1 kilogram, so we must divide the grams by 1000 to convert to kilograms. This means that 2.5 x 10⁶ g is equivalent to 2.5 x 10⁶ g x 10⁻³ kg/g = 2.5 x 10³ kg.
Now, both quantities are in kilograms, so we can add them together:
1.26 x 10⁴ kg + 2.5 x 10³ kg = (1.26 + 0.25) x 10⁴ kg = 1.51 x 10⁴ kg.
Thus, the sum in kilograms, using proper scientific notation, is 1.51 x 10⁴ kg.