Hey
Matter can neither be created nor destroyed.
Explanation:
This is the law of conservation of matter (mass). One can prove this by performing a simple experiment at home.
Have a great day
what started the wildfires
Answer:
It is a typical fires that started out of a lightning strike, or people carelessly starting it, or accidentally, or even arson, that went un-noticed and got out of hand.
Answer:
Explanation:
Forest fires always start by one of two ways - naturally caused or human caused. Natural fires are generally started by lightning, with a very small percentage started by spontaneous combustion of dry fuel such as sawdust and leaves. On the other hand, human-caused fires can be due to any number of reasons.
What mass of chromium would be produced from the reaction of 57.0 g of potassium with 199 g of chromium(II) bromide according to the following reaction? 2 K + CrBr2 2 KBr + Cr *
Answer:
38g of Cr
Explanation:
Step 1:
The balanced equation for the reaction:
2K + CrBr2 —> 2KBr + Cr
Step 2:
Determination of the masses of K and CrBr2 that reacted and the mass of Cr produced from the balanced equation.
This is illustrated below:
Molar mass of K = 39g/mol
Mass of K from the balanced equation = 2 x 39 = 78g
Molar Mass of CrBr2 = 52 + (80x2) = 212g
Mass of CrBr2 from the balanced equation = 1 x 212 = 212g
Molar Mass of Cr = 52g/mol
Mass of Cr from the balanced equation = 1 x 52 = 52g
From the balanced equation above,
78g of K reacted with 212g of CrBr2 to produce 52g of Cr.
Step 3:
Determination of the limiting reactant.
This is illustrated below:
From the balanced equation above,
78g of K reacted with 212g of CrBr2.
Therefore, 57g of K will react with = (57 x 212)/78 = 154.92g of CrBr2.
From the above calculation, we can see that a lesser mass (i.e 154.92g) than what was given ( i.e 199g) of CrBr2 is needed to react completely with 57g of K. Therefore, K is the limiting reactant and CrBr2 is the excess reactant.
Step 4:
Determination of the mass of Cr produced by the reaction.
In this case, the limiting reactant will be use because it will give the maximum yield of Cr as all of it is used up in the reaction process. The limiting reactant is K and the mass of Cr produced is obtained as follow:
From the balanced equation above,
78g of K reacted to produce 52g of Cr.
Therefore, 57g of K will produce = (57 x 52)/78 = 38g of Cr.
Therefore, 38g of Cr is produced from the reaction.
In general, when a substance changes from a solid to a liquid,
A.
the density of the substance increases.
B.
the substance no longer has density since density is a property only solids have.
C.
the density of the substance decreases.
D.
the density of the substance remains the same.
Answer:
c,density is the measure of compactness in a substance. Liquid particles are close together however they aren't as close as the particles in solids.
What is the oxidation half-reaction for this unbalanced redox equation? cr2o72– + fe2+ → cr3+ + fe3+ cr3+ → cr2o72– cr2o72– → cr3+ fe3+ → fe2+ fe2+ → fe3+?
Answer:
6Fe^2+(aq) -------> 6Fe^3+(aq) + 6e
Explanation:
The balanced oxidation half equation is;
6Fe^2+(aq) -------> 6Fe^3+(aq) + 6e
A redox reaction is actually an acronym for oxidation-reducation reaction. Since the both reactions are complementary, there can't be oxidation without reduction and there can't be reduction without oxidation.
The main characteristic of redox reactions is that electrons are transferred in the process. The number of electrons transferred is usually deduced from the balanced reaction equation. For this reaction, the balanced overall reaction equation is;
Cr2O7^2–(aq) + 6Fe^2+(aq) +14H^+(aq)→ 2Cr^3+(aq) + 6Fe^3+ (aq) + 7H2O(l)
It is clear from the equation above that six electrons were transferred. Thus six Fe^2+ ions lost one electron each in the oxidation half equation as shown in the balanced oxidation half equation above.
How many grams of H20 will be formed when 32.0 g H2 reacts with 16.0 g
O2? *
2H2 + O2 + 2H2O
9.00 g
16.0 g
18.0 g
32.0g
Answer:
18.0 g
Explanation:
M(H2) = 2.0 g/mol
32.0g * 1 mol/2 g= 16 mol H2
M(O2) = 32 g/mol
16.0 g * 1mol/32 g= 0.5 mol O2
2H2 + O2 ---> 2H2O
from reaction 2 mol 1 mol
given 16 mol 0.5 mol
We see that O2 is a limiting reactant.
2H2 + O2 +-------> 2H2O
from reaction 1 mol 2 mol
given 0.5 mol x mol
x =(0.5*2)/1= 1 mol H2O
M(H2O)= 18 g/mol
18 g/mol* 1 mol = 18 g H2O
How many milliliters of 0.2 M NaOH are required to exactly neutralize 40 milliliters of 0.1 M HCl?
A) 10
B) 20
C) 40
D) 80
Answer:
Option B. 20mL
Explanation:
Step 1:
Data obtained from the question.
Volume of base (Vb) =..?
Molarity of base (Mb) = 0.2M
Volume of acid (Va) = 40mL
Molarity of acid (Ma) = 0.1M
Step 2:
The balanced equation for the reaction.
HCl + NaOH —> NaCl + H2O
From the balanced equation above, the following were obtained:
Mole ratio of the acid (nA) = 1
Mole ratio of the base (nB) = 1
Step 3:
Determination of the volume of base, NaOH needed for the reaction. This is illustrated below:
MaVa/MbVb = nA/nB
0.1 x 40 / 0.2 x Vb = 1
Cross multiply
0.2 x Vb = 0.1 x 40
Divide both side by 0.2
Vb = 0.1 x 40 / 0.2
Vb = 20mL
Therefore, the volume of the base is 20mL.
The pressure of a gas in a cylinder when it is heated to a temperature of 250k is 1.5 atm. What was the initial temperature of the gas if it’s initial pressure was 1 atm?
Answer:
[tex]T1=166.66K[/tex]
Explanation:
According to Gay-Lussac’s law simply states that the ratio of the initial pressure and temperature is equal to the ratio of the final pressure and temperature for a gas of a fixed provided that the mass is kept at a constant volume.
Given:
Initial pressure, P1 = 1 atm
Final pressure, P2 = 1.5 atm
Final temperature, T2 = 250 K
The law can be applied using the below formula
P1T2 = P2T1
Then,
T1 = (P1T2)/P1 = (1*250)/(1.5) = 166.66 Kelvin.
[tex]T1=166.66K[/tex]
:
Answer:
[tex]T_1=166.7K[/tex]
Explanation:
Hello,
In this case, by applying the Gay-Lussac's law which help us to understand the pressure-temperature gas behavior via a directly proportional relationship:
[tex]\frac{P_1}{T_1} =\frac{P_2}{T_2}[/tex]
In such a way, as we are asked to compute the initial temperature knowing the initial pressure and final both temperature and pressure, so we solve for it:
[tex]T_1=\frac{T_2P_1}{P_2}=\frac{250K*1atm}{1.5atm} \\\\T_1=166.7K[/tex]
Best regards.
If the following weights have masses of 2, 4, 6 and 8 kg,
respectively, and they are at the same temperature, which one
will transfer more heat if they are all placed in cold water to
cool down? Explain.
Unit is calorimetry
Answer:
8 kg mass
Explanation:
As we can see in the image the weight of mass 8 kgs has a large surface area as compared to the surface area of other masses. In general, it has been observed that a wide surface area has more surface particle for heat conduction. Hence, the rate of heat transfer is directly proportional to the surface area of heat conducting surface. Thus, the larger the surface area, the faster is the rate of heat conduction.
Hence, weight of mass 8Kg wil transfer heat a fast rate.
1 point
If the pressure in a cylinder is 1 atm and the volume is 0.725 liters, then
what is the pressure when the volume is decreased to .075 liters (at
constant temperature)? *
2.5 atm
5 atm
5 atm
9.7 atm
O
13.2 atm
Answer:
9.7 atm.
Explanation:
The following data were obtained from the question:
Initial pressure (P1) = 1 atm
Initial volume (V1) = 0.725 L
Final volume (V2) = 0.075 L
Final pressure (P2) =?
The final pressure can be obtained by using the Boyle's law equation since the temperature is constant. This is illustrated below:
P1V1 = P2V2
1 x 0.725 = P2 x 0.075
Divide both side by 0.075
P2 = 0.725 / 0.075
P2 = 9.7 atm.
Therefore, the new pressure is 9.7 atm.
why is the international space station in orbit
Answer:
The ISS provides a location in the relative safety of low Earth orbit to test spacecraft systems that will be required for long-duration missions to the Moon and Mars.
Explanation:
mutations that neither benefit nor harm the organism have (blank) effect on the organisms survival
Answer:
I would say that the mutation has no effect on the organism, as it doesn't help or harm it.
hope this helps :)
Explanation:
Answer:
its a neutral
Explanation:
i did the test
If I add water to 100mL of a 0.15M NaOH solution until the final volume is 150mL, what will the molarity of the diluted solution be?
A. 0.100M
B. 1.2M
C. 0.01M
D. 52.8M
Answer : A
0,15 moles of NaOH -------in-------1000ml
x moles of NaOH ---------in-------100ml
x= 0,015 moles of NaOH
final volume =150ml
0,015 moles of NaOH -------in------150ml
x moles of NaOH ------in--------1000ml
x= 0,1 moles of NaOH
HELPPPP PLEASEEEE NAME THESE MOLECULES PLEASEEE
Answer:
1. carboxylic acid
2. ether
3. aldehyde
4. ketone
5. amine
6. alcohol
Explanation:
Know the functional groups. If you would like me to teach you them let me know.
- Hope that helps! Please let me know if you need further explanation.
In CaSO4, the oxidation number of Ca is
that of S is
and that of O is
Answer: In CaF2, the oxidation number of Ca is +2
, and that of F is -1
. In H2SO4, the oxidation number of H is +1
, that of S is +6
, and that of O is -2
. In CaSO4, the oxidation number of Ca is +2
, that of S is +6
, and that of O is -2
. In HF, the oxidation number of H is +1
, and that of F is -1
What type of elements are ionic bonds composed of?
Answer:
A metal and a nonmetal
Explanation:
Picture NaCl, the most famous example of an ionic compound. Two ions, Na+ (sodium) and Cl- (chlorine) are joined by an ionic bond.
Sodium, the metal, gives up an electron to chlorine.
Chlorine, the nonmetal, accepts an electron from sodium.
That way both have 8 electrons in their outer shell! This is the way ionic bonds function.
Using the equation below, calculate the approximate moles of oxygen gas (O2) required to completely react with 719.68 moles of aluminum (Al). 4Al (s) + 3O2(g) -----> 2Al2O3(s)
Answer:
539.76 moles of O₂
Explanation:
Equation of reaction:
4Al + 3O₂ → 2Al₂O₃
From the equation of reaction above, 4 moles of Al will react with 3 moles of O₂
We can use mole-concept to find the number of moles of O₂.
4 moles of Al = 3moles of O₂
719.68 moles of Al = x moles of O₂
X = (3 × 719.68) / 4
X = 2159.04 / 4
X = 539.76 moles
539.76 moles of O₂ will react with 719.68 moles of Al
Answer:
[tex]n_{O_2}=959.57molO_2[/tex]
Explanation:
Hello,
In this case, given the reaction:
[tex]4Al (s) + 3O_2(g) \rightarrow 2Al_2O_3(s)[/tex]
Since aluminum and oxygen are in a 4:3 molar ratio, we compute the moles of oxygen that completely react as shown below:
[tex]n_{O_2}=719.68molAl*\frac{3molO_2}{4molAl} \\\\n_{O_2}=959.57molO_2[/tex]
Best regards.
I have 345mL of a 1.5M NaCl solution. If I boil the water until the volume of the solution is 250mL, what will the molarity of the solution be?
A. 28.5M
B. 1.07M
C. 2.07M
D. 1.5M
what is the correct formula for the compound platinum (vi) flouride?
Answer: PtF6
Explanation: is one of seventeen known binary hexafluorides.
46g of a mineral contained 16g copper, 14g iron and 16g sulphur. Calculate the empirical
formula of the mineral.
Answer:
CuFeS2
Explanation:
Calculate the moles of each substance by doing moles= mass/relative atomic mass. you should get 0.25 moles of copper and iron and 0.5 moles of sulfur. Then divide all of those numbers by 0.25 (as its the lowest value) you should get 1 for copper and iron and 2 for sulfur. This represents the ratio that they are in within the mineral.
Which 1.0 M solution has the lowest pH?
A.
HCN
B.
H3PO4
C.
H2C2O4
D.
HCl
Which correctly defines a basic solution? A. [H+] is not present. B. [H+] is equal to [OH−]. C. [H+] is less than [OH−]. D. [H+] is greater than [OH−].
Answer: A basic solution is defined as a solution which has more hydroxide (OH-) ions than hydronium ions (H+)
In most mirrors, the virtual image appears to come from behind the mirror. True False
Answer
False
Explanation:
What are some true statements about light
Answer:It allows us to see things so we know where we are going that’s why at night we had lamp posts
Explanation:
Is the same reactant always the limiting reactant?
Why does dew form on the outside of your glass filled with ice cold water?
Most solutions are ___ solutions.
A heterogeneous
B saturated
C static
D unsaturated
Answer:
the answer is A heterogeneous solutions
Explanation:
Mixtures in two or more phases are heterogeneous mixtures. Examples include ice cubes in a drink, sand and water, and salt and oil. The liquid that is immiscible form heterogeneous mixtures. A good example is a mixture of oil and water.Jun 26, 2019
what 3 classes of compounds are elecrolytes
Answer:
i believe it is strong acids, strong bases, and salts.
Explanation:
Hope this helps : )
In the graph above for the dissociation of a strong acid, why do the bars for H3O+ and A- have the same height as the bar for HA?
Answer:
The concentration of HA is the same as concentration of H3O+ and A- produced.
Explanation:
The dissociation equation is given below:
HA(aq) + H2O (l) —> H3O+(aq) + A-(aq)
From the reaction above, we can see that the acid is monoprotic acid i.e it has only 1 ionisable hydrogen atom.
Now, from the balanced equation, we can see that the acid produced equal concentration of H3O+ and A-.
This account for the reason why the bars for H3O+ and A- have the same height as the bar for HA.
Which one is it? Please help
Answer:
Chemical properties can be tested without changing the substance
Explanation:
One of the biggest news stories of 1996 was the successful cloning of Dolly the sheep. Dolly was the first mammal cloned from an adult body cell. At first, Dolly appeared to be perfectly healthy. However, she died at age 6 of cancer. Dolly’s early death made scientists wonder whether cloned animals age faster than normal. A small flock of sheep cloned from Dolly have been observed since 2007. Happily, these clones show no sign of early aging. Choose the best option to complete the sentence. Scientists worried that cloned animals would age rapidly because their cells contain __________________ as old as the individual they were cloned from.
Answer:
I believe the answer you're looking for is DNA, not sure though
