What is the solution to the problem expressed to the correct number of significant figures?
7.21= ?
A. 1.688
OB.
1.69
O C.
1.7:
OD
1.70
Answer:
(102 900 ÷ 12) + (170 × 1.27) = 8800
Step 1. Evaluate the expressions inside the parentheses (PEMDAS)
102 900 ÷ 12 = 8575
170 × 1.27 = 215.9
In multiplication and division problems, your answer can have no more significant figures than the number with the fewest significant figures.
Thus, the underlined digits are not significant, but we keep them in our calculator to avoid roundoff error.
Step 2. Do the addition (PEMDAS).
8575
+ 215.9
= 8790.9
Everything that you add to an insignificant digit gives an insignificant digit as an answer.
Thus, the underlined digits are not significant.
We must drop them and round up the answer to 8800.
Explanation:
what type of galaxy is this
Explanation:
it is an spiral as it are rounded so
It is a spiral type of galaxy.
(Science) Help Please!
Answer:
product
Explanation:
It is the right answer.
What is the charge on an atom after it gains two electrons during the formation of a bond?
One negative charge
One positive charge
Two negative charges
Two positive charges
Answer:
two negative charges is the answer of your question
The equation for the complete combustion of ethene (C 2 H 4 ) is C 2 H 4 + 3O 2 2CO 2 + 2H 2 O If 2.70 mol of C 2 H 4 reacted with 6.30 mol , O 2 a. Identify the limiting reagent. b. Calculate the moles of water produced .
Answer:
22
Explanation:
HELP PLEASE , ITS DUE BY 6 ❤️10. If temperature were increased at the same rate for all four substances, which substance
would turn into a gas first?
Answer:
Dependant
Explanation:
Depending on the kind of substance you have (since ur answer of what substances was vauge) you would want to look at the molecular structure of the substances.
Understanding intermolecular bonds are key here (research this)
For example, Bromine is found as Br2 and only exerts London dispersion forces as there is no difference in polarity. And because this force is weaker, it has a lower boiling point
Another example being something like Hydrochloric acid (HCl). This is where Hydrogen acts as the positive atom while chlorine is the negative atom. This creates a stronger force and thus, a higher boiling point than Br2
Finally, there is Something like H2O where the force in play is Hydrogen bonding as Nitrogen, Oxygen, Fluorine where the bonds are strongest due to the electronegativity is at the greatest difference between these and Hydrogen. and thus having a higher boiling point.
So depending on the substance's bond, that will help determine the boiling point. If they fall under the same group, go based on the greatest difference in electronegativity.
I don't know if this is what you're looking for but, hope this helps. :)
A volcano erupts sending lava down its side the lava destroys the forest below which sphere is being impacted negatively? And why
PLEASE HELP ME I DONT HAVE MUCH TIME
Answer:
Biosphere
Explanation:
This is because the biosphere is the category of life. This means that plants, animals, humans, and bacteria are all apart of the biosphere.
A reaction that proceeds more slowly than
another reaction has a
(2 words)
______________
If the atomic number of an element is 8 and the mass number is 16, the number of neutrons in an atom of that element is what? (show work)
Answer:
8.
Explanation:
Atomic number tells us the number of protons in an element. Mass number is the total amount of mass in an atom, and it comes from the sum of the mass of protons and neutrons, which are both considered to have a mass of 1 amu.
If the total mass is 16amu and 8amu comes from the 8 protons, the remaining mass comes from neutrons.
16 - 8 = 8
Severe storms all have extremely strong winds that can cause a lot of environmental damage.
Which storm below has the strongest winds?
Which om sled below is amplo dl an abelis laeler in an evünment?
ban
B. droganty
C. ar temperatura
D. cation
Answer:
Explanation:
i got D
Please help with this question
THE ANSWER IS c:0%
HOPE IT MAY HELPS YOUhow much heat is released as 5.00G of PB cool from 75.0° C to 25.0° C
Answer:
32.25 J
Explanation:
Heat, H = ?
Mass, m = 5g = 5 / 1000 = 0.005 Kg
Initial Temperature = 75.0° C
Final Temperature = 25.0° C
Temperature change, ΔT = Final - Initial = 50° C
Specific heat capacity of lead, C = 129 (J/kg°C)
The relationship between these quantities is given by the equation
H = mCΔT
H = 0.005 * 129 * 50
H = 32.25 J
What is the molarity of a solution that contains 3.66 mol KCl in 7.98 L solution?
Answer:
.4586M
Explanation:
It's simple, just devide the mol value by the volume value. So 3.66mol/7.98L=.4586M
What are the general trends in first ionization energy across a period (LR) within the
periodic table? From bottom to top within a group?
How to do dots and cross diagrams
Answer:
Draw circles to represent the electron shell of each atom overlapping the circles where the atoms are bonded. Add dots to represent the outer electrons of one type of atom (H). Add crosses to represent the outer electrons of the other type of atom (Cl). Make sure the electrons are always in pairs.
What type of reaction is shown here?
C3H2O + 4023 CO2 + 3 H2O
Answer: combustion and girl
Explanation: C3H6O + 4 O2 → 3 CO2 + 3 H2O COMBUSTION
Which condition would cause an increase in the salinity of ocean water?
thawing of glaciers
high rates of evaporation
cold weather
a river flowing into the sea
Answer:
high rates of evaporation
Which of the following pairs of groups of elements cannot form ionic bond? *
IA & VIIA
IA & VA
VIIA & VIIIA
IIA & VIA
Answer:
pq ning kamot oi
Explanation:
hahahsfdydn ebejkakbabaha
I’ll really appreciate it if you help me out on these 2 questions.
Answer:
13. A
14. C
Explanation: i tried my best
why is respiration considered an exothermic process
Answer:
Respiration is considered as exothermic reaction because energy is released in this process. Glucose combines with oxygen present in our cells to form carbon dioxide and water along with energy.
Explanation:
Good Luck!
Respiration is considered as an exothermic reaction because, in the respiration process, oxidation of glucose takes place which produces a large amount of heat energy stored in the form of ATP. This is shown in the following chemical equation C 6
Question 5 of 5
When planning space exploration, scientists face many
challenges. One issue is the weight of the items being
transported. They can use the engineering design process
to help minimize the weight of materials on board a
spacecraft.
You have designed a prototype of a new, lighter material. What should be the
next step in your process?
A. Update your initial design for the new type of material.
B. Test to see
whether your material is strong and works well.
C. Figure out what problems people want to solve.
D. Brainstorm new ways to design materials.
Answer:B
Explanation: got it right on test
Test to see whether your material is strong and works well should be the next step in your process. Therefore, the correct option is option B.
What is space exploration?Space science and technology are used in space exploration to learn more about the universe. While astronomers use telescopes to explore the universe, both unmanned robotic space missions and human spaceflight also participate in the physical exploration of space.
When planning space exploration, scientists face many challenges. One issue is the weight of the items being transported. They can use the engineering design process to help minimize the weight of materials on board a spacecraft. You have designed a prototype of a new, lighter material. Test to see whether your material is strong and works well should be the next step in your process.
Therefore, the correct option is option B.
To know more about space exploration, here:
https://brainly.com/question/12271960
#SPJ5
Which is not an example of mechanical energy used in power plants? *
wind
water
O burning fossil fuels
O gravity
burninh fossil fuels is not an example
Answer:
Gravity
Explanation:
Gravity is not a form of mechanical energy used in power plants
Is the bond C=O polar or non polar
Answer:
Non Polar
Explanation:
Non Polar molecule because of its linear symmetric shape
When a new substance has formed, has a physical or chemical) change occurred?
(4 Points)
A) chemical
B) physical
Answer: A) Chemical Change
Explanation:
A chemical change create a NEW type of matter that CANNOT be reversed!
Example: Spolied milk
Example: Green tomatoe turns red
Hope it’s helpful! :)
1)Change the following temperatures to Kelvin: 100 C and -20 C
2)Change the following temperatures to Celsius: 273 K and 15 K
Answer:
373 K; 253 K
0°C ; -258°C
Explanation:
In order to change Temperatures to Absolute Value (Kelvin) you shoud do this sum:
T° in C + 273 = T° in K
For question 1:
100°C + 273 = 373K
-20°C + 273 = 253K
For question 2:
T° K - 273 = T° C
273 K - 273 = 0°C
15 k + 273 = -258 °C
Answer:
-67.8
Explanation:
As the moon orbits the ______________, its gravitational pull is______________ on the side of the earth closest to the ______________.This ______________ force pulls on the water facing the moon,creating a ______________. The moon also ______________ on the solidearth, causing the water on the far side of earth to ______________as well. These bulges in the water are the ______________.The areas in between the close and far side of the earth which are not in ______________ with the moon experience ______________.
pls help i give brainlyest
Answer:
Earth
Strongest
Moon
Gravitational
Tide
Pulls
Bulge
Waves
Proximity
Low Tide
how would I solve this problem?
Answer:
D
Explanation:
The goal in this set up is to make sure all units cancel each other.
Since we need to go from grams to atoms, our final unit should be atoms.
Using method of elimination, let's see why other options are wrong.
A - Although 'g' is cancelled out, we are left with moles^2 / atoms
B - Although 'g' is cancelled out, we are left with moles^2 / atoms
C - Although 'mol' is cancelled out, we are left with g^2 / atoms
What volume will 3.50 mol of ammonia gas occupy at conditions of standard temperature and pressure?
Answer:
Q:
What volume will 3.50 mol of Xe gas occupy at STP?
A:
78.4 L
Explanation:
The volume occupied by 3.5 moles of ammonia gas at standard temperature and pressure (STP) is 78.45 L
Data obtained from the question Number of mole (n) = 3.5 moles Pressure (P) = STP = 1 atm Temperature (T) = STP = 273 KGas constant (R) = 0.0821 atm.L/Kmol Volume (V) =? How to determine the volume
The volume of the gas at standard temperature and pressure (STP) can be obtained by using the ideal gas equation as illustrated below:
PV = nRT
1 × V = 3.5 × 0.0821 × 273
V = 78.45 L
Learn more about ideal gas equation:
https://brainly.com/question/4147359
If a star is 300 light years away from Earth, how long does it take light from that star to reach Earth?
A. 300 days
B. 300 hours
C. 300 years
D. 300 light years