Explanation:
The half-life is the time taken for a radioactive substance to decay to half of its original composition.
Let us assume that the original amount is x atoms;
Half - life = 60days
Days Composition Half-life number
0 x 0
60 x/2 1
120 x/4 2
180 x/8 3
240 x/16 4
300 x/32 5
360 x/64 6
The fraction that would be left after 360 days will be [tex]\frac{1}{64}[/tex]
What type of crust is colliding?
Japan Trench
Eurasian Plate
Pacific Plate
Answer: The Eurasian Plate or both the Eurasian and Pacific Plate.
Explanation:
Measure that affects the thermal energy of matter but not it's temperature.
Answer: mass
Explanation:
Copper metal reacts with silver nitrate to produce silver metal and copper (II) nitrate.
the correct equation for this reaction is:
A: Cu + SiN—> Si + Cu2N
B: 2Cu + AgNO3–> Ag +
Cu(NO3)2
C: Cu + 2 AgNO3–> Ag + Cu(NO3)2
D:Cu + AgNO3–> Ag + CuNO3
Answer:
Cu + 2AgNO₃ → 2Ag + Cu(NO₃)₂
Explanation:
The reactants are:
Copper metal = Cu
Silver nitrate = AgNO₃
The products are:
Silver metal = Ag
Copper (II) nitrate = Cu(NO₃)₂
So, the reaction equation is given as;
Cu + 2AgNO₃ → 2Ag + Cu(NO₃)₂
This is a single displacement reaction
the gravitational force between two objects depends on the distance between the objects and each object?
Answer:
Gravitational force between two objects depends on: a. The weight of the objects c. The mass of each object b. The distance between the objects d. Both b and c Please select the best answer from the choices provided A B C D
✓d
The average atomic mass for germanium is 72.631 amu. If germanium occurred as a mixture of the two isotopes below, what would be the percent abundance of 73Ge in the mixture?
mass of 70Ge = 69.924 amu
mass of 73Ge = 72.923 amu
Percent abundance of 73Ge in nature = ________ %
Answer:
dora needs help
Explanation:
Answer:
...........................
An increase in aurora activity on Earth could be related to what activity on the Sun?
O A decrease in prominence
B decrease in solar Fares
Oc decrease in speed of solar wind
D increase in speed of solar wind
E increase in sun spots
Answer:
D.
Explanation:
INCREASE OF SOLAR WINDS When the sun is more active
PLZ HELP IT BEING TIMED!!!!!! PLZ ANSWER!!!!!
Answer:
YIKES. a bit late. Answers include 1, 2, 3
Explanation:
We can draw three inequivalent Lewis structures for the sulfite ion , SO32- . The concepts of formal charge and electronegativity can help us choose the structure that is the best representation. 1. Assign formal charges to the elements in each of the structures below. Note: Count oxygen atoms starting from the left for each structure. A B C Formal Charge S O1 O2 O3 2. The best Lewis structure for SO32- is
Answer:
1. The Lewis structure for SO32- is structure B.
Note: See attachment for complete question and for formal charges of the atoms in each structure.
Explanation:
The formal charge of an atom in a molecule is the assumed charge the atom would have if the electrons in the bonds were evenly distributed between the atoms.
Formal charge can be calculated as follows:
Formal charge = number of valence electrons - ( number of non-bonding electrons + ½ bonding electrons)
Formal charges are used to determine the best possible Lewis structure of a molecule or ion. The following rules are applied:
1. A structure in which all formal charges are zero is preferable to one in which some formal charges are not zero.
2. If non-zero formal charges must exist in the structure , the arrangement with the smallest non-zero formal charges is most preferred.
3. Lewis structures are preferable when adjacent formal charges are zero or of the opposite sign.
4. The structure with the negative formal charges on the more electronegative atoms is preferred among other structures of the molecule or ion.
From the above rules, structure B has negative charges on the more electronegative oxygen atoms and has more zero formal charges on the atoms. The central atom, sulfur also has a zero formal charge.
what is the mole fraction of cation in 1M of aluminium sulphate
The mole fraction of cation (Al)=0.4
Further explanationGiven
1 M of Aluminium sulphate
Required
The mole fraction of cation
Solution
Ionization of the Aluminum sulfate solution( assume 1 L solution ) :
mol Al₂(SO₄)₃ = M x V = 1 M x 1 L = 1 mol
Al₂(SO₄)₃⇒2Al³⁺ + 3SO₄²⁻
1 mol 2 mol 3 mol
From this equation, total mol in solution = 2+3 = 5 moles
Mol fraction Al(as a cation) :
= 2/5=0.4
If phosphofructokinase experienced a mutation that interfered with substrate binding, then what other enzyme is going to be most immediately impacted in terms of accessing substrate?
A. aldolase
B. fumarase
C. glucolactonase
D. hexokinase
Answer: A. aldolase
Explanation:
Phosphofructokinase, is an enzyme which is vital in the regulation of fermentation. It is involved in the glycolysis process.
When it experiences a mutation that was being interfered with the substrate binding, we should note that the enzyme that is going to be most immediately impacted in terms of accessing substrate is aldolase.
Diana has just completed a reaction that had a chemical change. Which two changes could be evidence of this change?
color and odor
color and shape
odor and density
shape and density
Answer:
I think its A im sorry if im wrong
Explanation:
Answer:
color and odor
Explanation:
Which chemical used to make explosives is a fertilizer-based explosive, but requires nitric acid as a component to be an explosive compound, and has a wide range of uses, including as a noncorrosive de-icing material for sidewalks?
a. Aluminum nitrate
b. Triacetone triperoxide (TATP)
c. Hexamethylene triperoxide diamine (HMTD)
d. Urea nitrate
Answer:
d. Urea nitrate
Explanation:
Urea nitrate is a fertilizer-based explosive that is produced in one step by reaction of urea with nitric acid. The is an exothermic reaction, therefore, necessary steps and precautions must be taken to ensure safety during the process. The equation of the reaction is given below:
(NH₂)₂CO (aq) + HNO₃ (aq) → (NH₂)₂COHNO₃ (s)
It is as easily-made explosive and can also be used as a catalyst in Diels-Alder reactions of aromatic amines.
In the presence of water, urea nitrate readily decomposes to its original components, urea and nitric acid.
On its own, urea is commonly used as a deicer for sidewalks as it is a noncorrosive de-icing material. However, it is a more costly method of deicing, compared to other methods and it is best used where water runs off into vegetation than into a water-body or a storm drain because of its high-oxygen demand which could result in its reducing the oxygen level of the water body. It It is readily found in nature (in our urine) and is also synthesized artificially. It has a very high nitrogen content, and is most often used as a nitrogen‐based fertilizer.
A photon has an energy of 2.78 x 1032 J. What is its wavelength?
Answer:
7.14 × 10^(-58) m
Explanation:
We are given;
Energy; E = 2.78 x 10^(32) J
Formula to find this energy is;
E = hc/λ
Where;
E is energy
h is Planck's constant with a constant value of 6.62 × 10^(-34) J/s
c is speed of light with a constant value of 3 × 10^(8) m/s
λ is wavelength
Making λ the subject, we have;
λ = hc/E
λ = (6.62 × 10^(-34) × 3 × 10^(8))/(2.78 x 10^(32))
λ = 7.14 × 10^(-58) m
What is the measure of the amount of dissolved salts in ocean water?
Answer:
Salinity
HOPE THIS HELPS! :)
Explanation:
100POINTS! ANSWER ALL 3 PARTS (look at the picture)
Answer:
Part 1-B
Part 2-D
Part 3-A
Answer:
1.B
2.D
3.A
Explanation:
.......................
in a double replacement reaction cesium chloride reacts with silver nitrate to produce silver chloride and
a cacl
b cs(no3)2
c agcs
d csno3
Answer:
CsNO₃
Explanation:
The reactants are:
Cesium chloride = CsCl
Silver nitrate = AgNO₃
Products:
Silver chloride = AgCl
The other product:
Now;
CsCl + AgNO₃ → AgCl + ?
The other product is CsNO₃
So;
CsCl + AgNO₃ → AgCl + CsNO₃
What is the only way to be certain that a chemical change has occurred
Answer:
New kinds of products forms and the reaction is not easily reversible.
Explanation:
The only way to be certain that a chemical change has occurred is by finding out if new kinds of products have been formed.
A chemical change is a change in which new kinds of matter is formed. It is always accompanied by energy changes.
The process is not easily reversible.
Examples of chemical changes are combustion, rusting of iron, precipitation and souring of milk.
Kp/Kc for reaction for the equilibrium, A(g) ⇌ C(g)+B(g), is _______.
(Kc is the equilibrium constant in terms of concentrations, Kp is the equilibrium constant in terms of pressures, R is the gas constant, T is the temperature)
Select one:
(RT)2
(RT)-1
(RT)-2
(RT)-1.5
RT
Kp/Kc = RT
Further explanationGiven
Reaction
A(g) ⇌ C(g)+B(g)
Required
Kp/Kc
Solution
For reaction :
pA + qB ⇒ mC + nD
[tex]\large {\boxed {\bold {Kc ~ = ~ \frac {[C] ^ m [D] ^ n} {[A] ^ p [B] ^ q}}}}[/tex]
While the equilibrium constant Kp is based on the partial pressure
[tex]\large {\boxed {\bold {Kp ~ = ~ \frac {[pC] ^ m [pD] ^ n} {[pA] ^ p [pB] ^ q}}}}[/tex]
The value of Kp and Kc can be linked to the formula '
[tex]\large {\boxed {\bold {Kp ~ = ~ Kc. (R.T) ^ {\Delta n}}}}[/tex]
R = gas constant = 0.0821 L.atm / mol.K
Δn=moles products - moles reactants or
number of product coefficients-number of reactant coefficients
For reaction :
A(g) ⇌ C(g)+B(g)
number of product coefficients = 1+1=2
number of reactant coefficients = 1
Δn= 2 - 1 =1
So Kp/Kc = RT
A gas has a boiling point of 175 celsius. At what kelvin temperature would this gas boil
Answer:
448
Explanation:
K =273+°c
K=273+175
K=448
How is thermal energy transferred during conduction? Check all that apply.
Thermal energy is transferred between particles that are not touching each other.
Thermal energy is transferred between particles that are in direct contact with each other.
Thermal energy is transferred between objects of different temperatures.
Themal energy is transferred between objects of the same temperature.
Themel energy is transferred from slow-moving particles to fast-moving particles.
Themal energy is transferred from fast-moving particles to slow-moving particles, .
Answer:
Option 2, 3, and also 6 btw
Explanation:
The other guy was wrong
Sulfur dioxide, SO2, is used in wine as an antioxidant, slowing the oxidation of ethanol
to ethanoic acid. To determine the SO2 content of a wine sample, sodium hydroxide
and sulfuric acid were added to ensure that all sulfur was present as SO2. A 20.00 mL
aliquot was then titrated against standardised iodine solution, using starch indicator.
Reaction occurred according to the equation:
SO2(aq) + 2H2O(l) + 12(aq) → 4H+ (aq) + 21- (aq) + SO42- (aq)
The end point was reached with 15.62 mL of 0.00501 M iodine solution. The
concentration (in M) of SO2 in the wine was ...
A)6.2 x 10-3
B)7.8 x 10-3
C)3.9 x 10-3
D)5.0 x 10-3
The concentration (in M) of SO₂ in the wine : c. 3.9 x 10⁻³
Further explanationGiven
Reaction
SO2(aq) + 2H2O(l) + I2(aq) → 4H+ (aq) + 21- (aq) + SO42- (aq)
Required
The concentration (in M) of SO2
Solution
Titration ⇒ mol SO₂ = mol iodine(I)
mol iodine :
=15.62 ml x 0.00501 M
=0.078256 mlmol
From equation, mol ratio of of SO₂ : I₂ = 1 : 1, so mol SO₂=0.078256
The concentration of SO₂(in 20 ml sample) :
M = n/V
M = 0.078256 mlmol/20 ml
M = 0.0039128
M = 3.9 x 10⁻³
Mr. Smith wanted to see if the color of light shined on a plant had an effect on the number of leaves it had. He gathered a 2
groups of the same species of plants, gave them the same amount of water, and did the test for the same amount of time.
On one group of plants he used white light. On the second group he changed the light color to red. Identify:
Independent variable:
Dependent variable:
Constants:
Control group (What would Mr. Smith use as a control group?):
Experimental group (what would Mr. Smith use as a experimental group?)
what is the mass in grams of 0.40 moles of sodium borohydride nabh4
Answer:
15.12g
Explanation:
Given parameters:
Number of moles = 0.4moles
Unknown:
Mass of the compound = ?
Solution:
To solve this problem;
Mass = number of moles x molar mass
Molar mass of NaBH₄ = 23 + 10.8 + 4(1) = 37.8g/mol
Mass of the compound = 0.4 x 37.8 = 15.12g
Answer:
The answer is 15.12 g but if you are taking this test on ck12 make sure you round it to 15 like it says on the directions :) good luck
what type of reaction is AsCl+H2S --> As2S3+HCl
Answer:
Double replacement:
Explanation:
Chemical equation:
2AsCl + 3H₂S → As₂S₃ + 6HCl
The given reaction is double displacement reaction. In this reaction arsenic trichloride and hydrogen sulfide react and produced arsenic sulfide and hydrogen chloride. In double displacement reaction both anion an cation of reactants are exchanged with each other.
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
General equation:
AB + CD → AD +CB
How many grams of Fe3+ are present in 2.56 grams of iron(III) iodide?
Answer:
436.55841 grams.
Explanation:
The molecular formula for Iron(III) Iodide is FeI3. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Iron(III) Iodide, or 436.55841 grams.
You use the 1 / 436.55841 conversion rate. This is different for each element, according to the stoichiometry tables. Iron(II) oxide would be 2/3 of the 1/436.55841 conversion rate, that is, multiplying the fraction to denominator.
The metal rhenium becomes superconducting at temperatures below 1.4 K. Calculate the temperature at which rhenium becomes superconducting in degrees Celsius.
Answer:
The temperature at which rhenium becomes superconducting is -271.6 ºC.
Explanation:
We can convert the temperature given in Kelvin, which is an absolute scale, into degrees Celsius. which is a relative scale, by a simple algebraic translation, that is:
[tex]T_{C} = T_{K} - 273[/tex] (1)
Where:
[tex]T_{C}[/tex] - Temperature, measured in degrees Celsius.
[tex]T_{K}[/tex] - Temperature, measured in Kelvins.
If we know that [tex]T_{K} = 1.4\,K[/tex], then the temperature given in degrees Celsius is:
[tex]T_{C} = 1.4\,K-273[/tex]
[tex]T_{C} = -271.6\,^{\circ}C[/tex]
The temperature at which rhenium becomes superconducting is -271.6 ºC.
HELPP! What is ammonium nitrates freezing point ?
Answer:
Freezing points for water with freezing mixtures based on salt and ice: Ammonium Nitrate - Chrushed Ice or Snow in Water 1 part Ammonium Nitrate - 0.94 parts Ice/water : temperature -4 o C 1 part Ammonium Nitrate - 1.20 parts Ice/water : temperature -14 o C
Explanation:
Peeling a banana is an example of a
A. no change
B. chemical change
C. physical change
Answer:
C. Physical Change
Explanation:
Peeling a banana is not changing the banana's structure, it's still the same banana, but it looks different, which is a chemical change! Hope I helped!
4NaOH + 4HCI - NaCl + H20
Answer:
NaOH + HCl —> NaCl + H₂O
Explanation:
From the question given above, we obtained the following equation:
4NaOH + 4HCl —> NaCl + H₂O
The equation can be balance as follow:
4NaOH + 4HCl —> NaCl + H₂O
There are 4 atoms of Na on the left side and 1 atom on the right side. It can be balance by putting 4 in front of NaCl as shown below:
4NaOH + 4HCl —> 4NaCl + H₂O
There are a total of 8 atoms of H on the left side and 2 atoms on the right side. It can be balance by putting 4 in front of H₂O as shown below:
4NaOH + 4HCl —> 4NaCl + 4H₂O
Next, divide through by 4 to express the equation with the lowest coefficients.
NaOH + HCl —> NaCl + H₂O
Now the equation is balanced.
NOTE: Smallest coefficients are always used to represent a balanced equation.
The currently accepted model of the atom includes an electron cloud.
A. True
B. False
Answer:
True
Explanation:
Answer: True
Explanation:
