Answer:
burning causes pollution cutting results furniture
Explanation:
are u a nepali ?
Answer:
burning of wood, new substances are formed and hence it is a chemical change. While cutting the wood into small pieces no new substance is formed, thus it is a physical change. Hence, burning of wood and cutting it into small pieces are considered as two different types of changes.
10 divided by 2 im confused
if your serious about this question then it is 5
3. Gold-198 decays with a half-life of 2.7 days according to the equation:198Au → 0−1β + 198Cd
a. Find the value of the rate constant, k. Include units.
b. How much of a 10.0 g sample of Au-198 remains after seven days? (Use the integrated rate law formula.)
a. k=0.256/day
b.sample of Au-198 remains after seven days : 1.67 g
Further explanation1. A half-life of 2.7 days⇒t1/2=2.7 days
The half-life can be expressed in a decay constant( λ)
[tex]\tt \displaystyle t_ {1/2} = {\dfrac {\ln (2)} {\lambda}}\\\\\lambda(or~k)=\dfrac{0.693}{2.7}=0.256/day[/tex]
2. We can use formula : (integrated rate law) :
[tex]\tt ln[A]=-kt+ln[Ao]\\\\ln(\dfrac{Ao}{A})=kt[/tex]
Ao=10 g
t=7 days
k=0.256/day
[tex]\tt ln(\dfrac{10}{A})=0.256\times 7\\\\ln(\dfrac{10}{A})=1.792\\\\e^{1.792}=\dfrac{10}{A}\\\\6=\dfrac{10}{A}\rightarrow A=1.67~g[/tex]
The mass of Au-198 that remains after seven days is 1.62 g.
We know that radioactive decay is a first order reaction hence;
k = 0.693/ t12
Where;
k = rate constant
t12 = half life
k = 0.693/ 2.7 days = 0.26 day-1
Using;
N =Noe^-kt
No = amount of radioactive material initially present
N = mass of radioactive substance present at time t
N = 10 e^-(0.26 × 7)
N = 1.62 g
The mass of Au-198 that remains after seven days is 1.62 g.
Learn more about radioactive decay: https://brainly.com/question/14077220
What data do scientists use to determine when a volcano might erupt?
Whoever gives me the right answer will get brainliest.
Answer:
seismographs
Explanation:
Scientists use seismographs that record the length and strength of each earthquake to try to determine if an eruption is imminent. Magma and gas can push the volcano's slope upward.
What is the largest limiting factor that keeps us
from traveling far away from Earth in space?
PLEASE HELP I WILL LOVE YOU FOREVER! I REALLY AM DUMB PLEASE! ANSWER FULL QUESTION FOR BRAINLIEST :D
The teacher told Fatima that all types of energy are kinetic energy, potential energy, or both. Fatima drew this diagram to help her organize this information. She then sorted each type of energy into its correct category: chemical, electrical, electromagnetic, mechanical, nuclear, and thermal. An illustration of a Venn diagram with the label Potential energy in the left circle, Kinetic energy in the right circle, and both in the shared middle part of the two circles. Three of the types of energy can be either kinetic or potential energy. Identify these three types. For each type, explain why it can be either kinetic or potential.
Answer: (D) Thermal
Explanation: This is Thermal because it is the only one that makes sense
PLEASE ANSWER ASAP
*Will mark *25 points
Question 5 of 5
The Monroe Doctrine changed the United States' role in the world by:
O A. allowing the country to control a huge number of colonies around
the world.
O B. increasing the country's power to influence political decisions in
Europe.
C. giving the country a larger role in protecting other countries in the
Americas.
D. forcing the country to use its military to support all democratic
revolutions.
Answer:It is C i got it correct
Explanation:
Answer:
C. giving the country a larger role in protecting other countries in the
Americas.
Explanation:
The work done by effort is called
Answer:
load
Explanation:
the load is the work done by the effort on the machine
Plz answer as soon as possible!!
Question: what is a shared pair of electrons? What is an unshared pair?
Answer:
Explanation:
shared pair of electrons= covalent bond (sharing of electrons allows atoms to complete octet and gain stability)
unshared pair of electrons= lone pair/ non-bonding pairs
what’s the answer please gelp
Answer:
Option A. 1.8×10²⁴ molecules.
Explanation:
Data obtained from the question include:
Number of mole of methane = 3 moles
Number of molecules of methane =?
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ molecules.
Thus, 1 mole of methane equally contains 6.02×10²³ molecules.
With the above information in mind, we can obtain the number of molecules in 3 moles of methane as follow:
1 mole of methane contains 6.02×10²³ molecules.
Therefore, 3 moles of methane will contain = 3 × 6.02×10²³ = 1.8×10²⁴ molecules.
Thus, 3 moles of methane contains 1.8×10²⁴ molecules.
The density of lead is 11.4g/cm3. What volume, in ft3, would be occupied by 10.0 g of lead?
Answer:
The volume is 3.09 ft^3.
Explanation:
The formula for volume is mass divided by density. 10.0 g / 11.4 g/cm^3 = 0.87719. Converted to cubis foot is 3.09 ft^3. I hope this helps you.
PLEASE HELP!!!!!!!!
Step 4: Create Lewis dot diagrams.
a) Draw Lewis dot diagrams of the reactants and products on the paper with your chemical equation.
b) Select a different color to use for each element in the chemical reaction. Use your chosen color
for the element’s symbol and for its valence electrons.
c) Label these diagrams “Lewis Dot Diagrams.”
Answer:
Hey student your question is not proper arrange, i don't understand what you want us to do
What is the term
chemistry
Answer:
Chemistry is the scientific study of the structure of substances, how they react when combined and how they behave under different situations.
Answer:
The branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.
Explanation:
Hope this helps!!!!!!
:)
12 Ethene gas, CH is completely burned in excess oxygen to form carbon dioxide and water
The equation for this exothermic reaction is shown.
CH 30, - 200, 2H,0
The table shows the bond energies involved in the reaction
bond
bond energy
(kJ/moly
614
413
C-C
CHH
0 0
СО
495
799
O-H
467
What is the total energy change in this reaction?
A-954 kJ/mol
B-1010 kJ/mol
C-1313 kJ/mol
D-1359 kJ/mol
Answer:
12 Ethene gas, CH is completely burned in excess oxygen to form carbon dioxide and water
The equation for this exothermic reaction is shown.
CH 30, - 200, 2H,0
The table shows the bond energies involved in the reaction
bond
bond energy
(kJ/moly
614
413
C-C
CHH
0 0
СО
495
799
O-H
467
What is the total energy change in this reaction?
A-954 kJ/mol
B-1010 kJ/mol
C-1313 kJ/mol
D-1359 kJ/mol
Explanation:
thats all you said
Which of the following diagrams correctly represents the formation of a compound consisting of magnesium and fluorine?
Answer:
See explanation
Explanation:
The image attached describes the formation of magnesium fluoride.
Magnesium has two valence electrons while fluorine has seven valence electrons. Magnesium can now transfer one electron each to two fluorine atoms thereby forming the compound MgF2.
This has been shown pictorially in the image attached to this answer.
Students in a chemistry lab used sodium hydroxide to neutralize the carbonic acid in two different sodas, coke and sprite. More base was required to neutralize the sprite than the coke. What does this tell you about the acidity of sprite as compared to coke?
A: Coke is more acidic than sprite
B: Sprite is more acidic than coke
C: Coke and Sprite are equally acidic
D: There is not enough information to determine
Gamma rays are often used to kill microorganisms in food, in an attempt to make the food safer. Some people contend that this irradiated
food is actually less safe to eat. Which, if true, would most effectively dispute their idea? (1 point)
a
Irradiated food only emits alpha particles, which are harmless.
Ob
Irradiated food is shown to not be radioactive.
C
Irradiated food only contributes to background radiation.
Irradiated food has molecules that undergo transmutation,
Od
Answer:
b . Irradiated food is shown to not be radioactive.
Explanation:
If it can be proven that irradiated food is not radioactive, then it will effective dispute the idea that irradiated food are less safe to eat.
An irradiated food is one in which ionizing radiations have been employed to improve food quality. Thus, bacteria and other food spoilers can be exterminated from the food. Most irradiated food do not contain radiation and are fit for consumption.If it can be proven, that this is true, then it will challenge the idea that irradiated foods are not safe.
Which part of the atom can be transferred from one atom to another to form
ions?
a. Protons
b. Neutrons
c. Valence Electron
d. Nucleus
Answer:
Explanation: Valance Electron
paragraph on water cycle
Answer:
The water cycle or hydrologic is a continuous cycle where water evaporates, travels into the air and becomes part of a cloud, falls down to earth as precipitation, and then evaporates again. ... These areas are usually close to oceans or large bodies of water that allow more water to evaporate and form clouds.
Explanation:
Please help me It would mean everything!!
1. high
You are correct.
Cold region have more air pressure because air is denser.
Thanksgiving is November 26th. Today is November 9th. How many seconds are there until Thanksgiving Day?
I WILL GIVE BRANLIEST HELP HELP HELP THE SUBJECT IS ACTUALLY SCIENCE What factor is a mushroom in an ecosystem? Abiotic or Biotic?
Answer: The answer is biotic
Explanation:Mushrooms are biotic because they are living things. Abiotic means non living, so these are factors in the environment that influence a living thing's life and chance of survival
Answer: jdusjzj bacteria germs
Explanation:
Which statement is true about your mass
A: you would have less mass on the moon
B:you would have less mass on earth
C: you would have more mass on earth
D: you would have the same mass on the earth and moon
The insect population competes for _______________________ and nectar.
Answer:
eachother or different type of flower
Explanation:
Use the drop-down menus to select the sentences that show precise use of pronouns.
1. Fred visited Nick after his graduation.
2. After Nick's graduation, Fred visited him.
1. Marie told Sarah that she makes great spaghetti.
2. Marie told Sarah, "You make great spaghetti."
1. John broke the fence with his bike.
2. John's bike hit a fence and it broke.
Answers
Sentence 1
Sentence2
Answer:
sentence 2, sentence 2, sentence 1
Explanation:
it was right for me on edge 2020
Answer:
1. Fred visited Nick after his graduation.
2. After Nick's graduation, Fred visited him.
1. Marie told Sarah that she makes great spaghetti.
2. Marie told Sarah, "You make great spaghetti."
1. John broke the fence with his bike.
2. John's bike hit a fence and it broke.
What is the volume of a 86.8 gram Piece of aluminum? The density of aluminum is 2.70g/mL.
Answer:
The answer is 32.15 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\ [/tex]
From the question we have
[tex]volume = \frac{86.8}{2.70} \\ = 32.148...[/tex]
We have the final answer as
32.15 mLHope this helps you
Fe (s) + Pb(NO3), (aq) —> ___
Type of reaction: _____
Answer:
lead , chemical
Explanation:
My teacher is grading this soon can someone help me ASAP!
10. You demonstrated the difference in density of the two objects. It is a physical property.
11. First calculate the density for all of them: density = mass/volume
Density:
A. 5/6 g/ml
B. 10/9 g/ml
C. 15/16 g/ml
D. 20/10 g/ml
If the density of the substance is higher than the density of the substance it is put in, then it will sink. So substances B and D will sink in water, as their densities are higher than 1 g/ml.
12. Ammonia weighs less than water does-- for example, the weight of 8 gallons of ammonia will be equivalent to the weight of 5 gallons of water.
Hope this helped!
What is necessary to produce visible light from chemical compounds?
Answer:
the molecule must contain either pi bonds or atoms with non-bonding orbitals.
Explanation:
A non-bonding orbital is a lone pair on, say, oxygen, nitrogen or a halogen.
What are the coefficients for the following chemical reaction?
___Be(BrO3)2 --> ___BeBr2+___O2
A.
1, 1, 3
B.
2, 2, 6
C.
2, 2, 3
D.
2, 1, 2
1 points
QUESTION 12
The previous question is an example of what type of chemical equation?
A.
Synthesis
B.
Decomposition
C.
Single Re-Placement
D.
Double Re-Placement
Explanation:
A and D. the answer is a and d
An atom of a certain element has 12 protons, 14 neutrons, and 2 valence electrons. What is the name of this element?
Given :
An atom of a certain element has 12 protons, 14 neutrons, and 2 valence electrons.
To Find :
The name of this element.
Solution :
We know, element with atomic number ( number of protons ) 12 and valance electrons is Magnesium.
Now, isotope of magnesium of proton with 14 neutrons is Mg-16 .
Therefore, name of element is Mg-16 .
Hence, this is the required solution.