Answer:
The letters are a one- or two-letter symbol assigned to each element.
Explanation:
If the half-life of Sulfate-12 is 18 years, how much of a 6 gram sample is left after 2 half-lives?
Answer:
The correct answer is - 1/4 0f 6 gram or 1.5 gram to be exact.
Explanation:
Given:
Half-life of sulfate-12 = 18 years
number of half-lives - 2
initial amount - 6 grams.
Solution:
The Half-life of an element or substance is the required time to decay the half amount of the initial amount of the element.
Remaining amount = initial amount * (1/2)^n
here n = number of half lives
then,
Remaining amount = 6* (1/2)^2
= 6/4
= 1.5 g.
Thus, the correct answer is = 1.5 g or 1/4 of 6 gram.
Which pure substance can be classified as an element?
Answer:
A substance that cannot be broken down into chemically simpler components is an element.
Aluminum, which is used in soda cans, is an element.
Which of the following is NOT a sign of a chemical change? (HINT: only 2 answers, the rest are chemical change)
1. tarnished is formed
2. gas is produced
3. weight change
4. Temperature change
5. color change
6. nothing changes
7. forms a precipitate
8. energy is released
Need this done today please!!
Answer:
3 and 6 (weight change and nothing changes)
Explanation:
Hi there!
A chemical change is a change when matter changes into a new substance and has a new chemical property.
The signs that a chemical change is taking place are:
1. change in color
2. change in smell
3. change in energy (for example, there is a change in temperature (thermal energy))
4. a gas is formed (fizzing/bubbling/foaming are signs of this!)
5. formation of a solid (a precipitate)
A physical change is any change to the size, shape, or state of a substance. The substance still has the same chemical property.
these are your eight options:
1. tarnished is formed (a sign of a chemical change; a change in color)
2. gas is produced (a sign of a chemical change)
3. weight change (NOT a sign of a chemical change. Even though the weight changed, the substance still has the same chemical composition and therefore, there wasn't any change to its chemical identity)
4. Temperature change (a sign of a chemical change; a change in energy)
5. color change (a sign of a chemical change)
6. nothing changes (NOT a sign of a chemical change. If nothing happens, the substance is still the same as it was originally and there was no change to its chemical identity.)
7. forms a precipitate (a sign of a chemical change)
8. energy is released (a sign of a chemical change)
therefore the two options that are NOT a sign of a chemical change are 3 and 6 (weight change and nothing changes)
Hope this helps! :)
Write the balanced chemical equation for the reaction of glucose (C6,H12,O6) with oxygen gas to produce carbon dioxide gas
and water vapor.
Answer:
C6H12O6+6O2=6Co2+6H2o
The balanced chemical equation for the reaction of glucose (C₆H₁₂O₆) with oxygen gas to produce carbon dioxide gas and water vapor is C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O
The balanced chemical equation is the equation in which the number of atoms on the left hand side that is reactant side is equal to the number of atoms on the right hand side that is product side in an equation.
The balanced chemical equation is:
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O
Thus, from the above conclusion we can say that The balanced chemical equation for the reaction of glucose (C₆H₁₂O₆) with oxygen gas to produce carbon dioxide gas and water vapor is C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O
Learn more about the Balanced Chemical equation here: https://brainly.com/question/26694427
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What is a likely result of an increase in average global temperatures on Earth?
A. More predictable weather
B. Rising sea levels
C. Fewer rainstorms and blizzards
D. Falling sea levels
Answer:
A.
Explanation:
Warmer temperatures can also lead to a chain reaction of other changes around the world. That's because increasing air temperature also affects the oceans, weather patterns, snow and ice, and plants and animals. The warmer it gets, the more severe the impacts on people and the environment will be.
Question 21
Which equation is a balanced chemical equation?
A
2NaOH + CaBr2 + Ca(OH)2 + NaBr
B
NO + Cl2 → NOCI
с
CaCO3 + CaO + 2CO2
D
2AlCl3 + 3Mg + 3MgCl2 + 2A|
D
B
Ос
ОА
Answer:
the equation is not correctly written but the answer is option D
The balanced equation among the given options is D, where each of the elements are equal in number on both side.
What is balanced reaction?A balanced chemical equation for a reaction represents perfect stoichiometric ratios of each reactants and products. Each elements have to be equal in number on both sides.
The number of elements or groups can be balanced each side by multiplying with suitable integers. The chemical equation in D is balanced where, Al, Cl and Mg are balanced on both side.
The equation in A, is not balanced where, number of Na and Br are not balanced. In equation B Cl is two in reactant side and one in product side. Thus, not balanced. Similarly in option C, oxygen and calcium are not balanced. Therefore, option D is correct.
To find more on balanced reactions, refer here:
https://brainly.com/question/14258973
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how many elements are in 3cacl2
energy the ability to do ____ or cause ____ its measured in _____ and is found in many different _____. energy can be classified as _____ or _____ energy
PLS HELP QUICK!!!!!
summarize what you know about carbon
Answer:
Carbon is a chemical element, like hydrogen, oxygen, lead or any of the others in the periodic table. Carbon is a very abundant element. It exists in pure or nearly pure forms – such as diamonds and graphite – but can also combine with other elements to form molecules.
HELP FAST PLS !!!!!!!!!!!!!!!!
Answer:
The Peruvian area of the jungle, living in the high trees is the monkey's habitat.
(I'm not fully sure what a niche is) but:
Feeding on hazelnuts and scavenging for food along the jungle floor is the monkey's niche.
Explanation:
I really hope I was able to help!
Good luck and have a great day :)
Please if any one know any question help me please
15. Which of the following elements will not form a polar covalent bond with oxygen? A. Sodium B. Fluorine Oxygen D. Hydrogen
Answer:
C. oxygen
Explanation:
oxygen cannot for a polar covalent bond with another oxygen atom
Answer:
oxygen
Explanation:
Complete the sentence!
Organisms in an ecosystem compete for _____. (Select all that apply).
A : shelter
B : water
C : food
D : space
Answer:
I personally think it would be all of the above
9. The prefix oct- means
That there are
8 hydrogen atoms
8 carbon atoms
8 single bonds
8 double bonds
Answer:
2nd option
Explanation:
it means that there are 8 carbons
The prefix oct- mean that there are 8 carbon atoms. Therefore, option (B) is correct.
What are the steps for the IUPAC nomenclature?The 1st step for the IUPAC nomenclature of a compound is to select the longest, most substituted carbon chain with a functional group. Then the use of the primary suffix indicates the degree of unsaturation such as 'ane' or 'ene.
Then the identification of the secondary suffix indicates the number of functional groups in the molecule and the number of times of the same functional group such as di, tri, tetra, etc.
The prefix can be used to indicate the side chains, substituents, and low-priority functional groups. The prefix Oct- is used if there are eight carbon atoms in the chain. The prefix 'ane' is used for single bonds and the prefix 'ene' is used for the double bonds in the carbon chain.
Learn more about IUPAC nomenclature, here:
brainly.com/question/2599286
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What method could be used to separate the
components of gasoline?
Answer:
Distillation
Explanation:
Reason being the process is only used to separate liquids with boiling points greater than 25 °C
Answer:
b
Explanation:
correct on edge
How many moles of Mercury ll oxide are needed to produce 125g of o2
What does it mean if an element has 8 valence electrons?
Answer:
the answer is the D, it has a full octet
PLEASE HELP PLS LFHLFATOI;RHG
Answer:
C. A model of a water molecule
Explanation:
H20, model shows 2 H,s (H2) and 1 O (O) which makes H2O. It's a model and not a real life picture of a molecule.
Answer:
C. A model of a water moleculeExplanation:
2 hydrogen + Oxygen= water molecule#CarryOnLearning
[tex]{.hope (it helps}}) [/tex]
which of the following is an alkaline earth metal?
A.Silicon (Si)
B.Aluminum (Al)
C.Carbon (C)
D.Magnesium (Mg)
2500 cal of heat are absorbed by 150 grams of water that is initially at 23°C, what is the final temperature of the water?
Answer:
H=MC∆T
Heat = Heat absorbed or given off
M=Mass
C=Specific Heat Capacity of substance (Water in thus case). It has a Specific Heat capacity of 4200J/kg.k
∆T= Temp Change (T2-T1)
I'll solve with My Heat in Joules.
The heat is given in Calorie
1Cal = 4.186J
2500cal = 10,465J.
∆T= H/MC
=10465/0.15(4200)
=16.6°C
∆T=16.6
T2 - T1 = 16.6
T2 = 16.6+T1
T2 = 16.6 + 23
T2 = 39.6
Approx. 40°C
Why does water appear blue?
A. Because the sky is reflecting on the water
B. Because of the way the water molecules are moving
C. Because of blue-colored elements dissolved in the water
Why does lead affect the brain and nervous system?
Answer:
Lead may disrupt the functioning of mitochondria in the developing brain. Because the mitochondria are important for energy production within a neuron, a change in their function may damage the cell. Lead may also affect brain function by interfering with neurotransmitter release and synapse formation.
shakajskwbskam help?
Answer:
beta
Explanation:
Why does CCl4 dissolve in iodine
Answer: They are both non polar molecules compounds although water is a polar molecule compound. There are no significant attractions.
Which sequence represents a portion of a
homologous series of hydrocarbons?
1.
C2H2, C2H4, C2H6
2.
C2H2, C3H4, C6H6
3.
C2H4, C3H4, C4H4
4.
C2H4, C3H6, C4H8
Answer:
4. C2H4, C3H6, C4H8
this is the alkane homologous series of hydrocarbons.
Their general formula is CnH2n
you can check this fits for all these compounds
put n = 1, 2, 3 and so on
What can a drop of liquid mercury be described as?
a pure substance and a compound
an impure substance that is reactive
an impure substance that is unreactive
a pure substance and an element
Answer:
a pure substance and an element”
Explanation:
An atom Q contains 19 electrons, 19 protons and 20 neutrons.
What is Q
Answer:
Potassium is the answer
Hydrogen bonding occurs when hydrogen is bonded to N, O, or F. Which of the following molecules has hydrogen bonding, when bonding with
their same molecules?
A. CBr4
O B.H2S
C. NO2
OD. NH3
Answer:
I think the answer is……
O B.H2S
Explanation:
I’m not sure tho, I’m just not 100% positive.
i need help asap please :) it says to “identify the reactants.”
the options are
A: Carbon Dioxide and water
B: Glucose and oxygen
C: sunlight and chlorophyll
The reactants are A: Carbon Dioxide and water
What is the molarity of a 6.48 L soda that contains 5.53 moles of sugar?
Answer:
0.853 M
General Formulas and Concepts:
Acid-Base Titrations
Molarity = moles of solute / liters of solutionExplanation:
Step 1: Define
Identify variables
[Given] 6.48 L
[Given] 5.53 mol
Step 2: Solve for Molarity
Substitute in variables: M = 5.53 mol / 6.48 LDivide: M = 0.853395Step 3: Check
Follow sig fig rules and round. We are given 3 sig figs.
0.853395 M ≈ 0.853 M