Explanation:
Since Z is EXPLICITLY determined by the number of protons, massive, positively charged particles, present in the element's nucleus, the proton must be the greatest determinant. Of course, it is the electrons that actually do the chemistry, but Z defines the element.
Which property altered during a chemical change is not altered during a physical change?
A. composition of the matter
B. temperature of the matter
C. volume of the matter
D. phase of the matter
The property altered during a chemical change that is not altered during a physical change is composition of the matter.
A physical change is one in which no new substance is formed and it is easily reversible.
A chemical change is one that is not easily reversible and no new substance is formed. It may be accompanied by absorption or evolution of heat.
The composition of a substance changes during a chemical change because bonds between atoms break and new bonds are formed. This does not occur during a physical change.
Learn more; https://brainly.com/question/11946229
calculate mass of MnO2 if 1 mole of KMnO4 completely burnt. 2KMnO4 -> K2MnO4+MnO2+O2
Answer: 80 grams
Explanation:
2KMnO4 -> K2MnO4+MnO2+O2
2 moles of KMnO4 would produce 1 mole of MnO2, so 1 mole of KMnO4 would produce 0.5 moles of MnO4. The molar mass of MnO4 is 160 g/mole. 1/2 mole of KMnO4 would therefore be (160 g/mole)*(0.5 moles) = 80 grams.
Am element has 18 electrons ,20 neutrons and a charge of -2.what is the mass number?..a.38 b.40 c.32 d.39
Answer:
Surely you must have a Periodic Table beside you....?
a=38
Explanation:
You gots Z=18, the atomic number, where Z is the number of nuclear protons. The number of protons defines the element....and thus we got calcium....
....and with 20 neutrons we got the 38Ca isotope....the which is rather short-lived...
6. Heat from the sun reaches to us by
(a) radiation
(b) conduction
(c) convection
(d) all of these
PS. the one who gets it correct will be followed by me and also be marked as the brainliest!
Answer:
radiation
....
.
.
.
.hi how r u
Is my answer correct
Answer:
Radiation
Explanation:
Heat from the sun reaches is by the process of radiation
How many inches are in 4.5 miles?
Hello please I need help
when two atoms share four valence electrons the shared electrons form a/an ____
for the equation given, how many grams of methane will react with a 125g of oxygen
CH4 (g) + 2O2(g) -> CO2(g) +2H2O
Answer:
16
Explanation:
1) in the given equation CH₄+2O₂⇒ 2H₂O+CO₂;
M(CH₄)=12+4=16 (g/mol); M(O₂)=32 (g/mol);
2) if m(O₂)=125 gr., then ν(O₂)=m(O₂)/M(O₂)=125/32≈3.90625 (moles);
3) if in the given equation 'ν' of O₂ is 2, then the 'ν' of CH₄ is 1;
4) m(CH₄)=ν(CH₄)*M(CH₄)=1*16=16 (gr.).
Loss of atmospheric ozone has led to an ozone "hole" over Antarctica. The process occurs in part by three consecutive reactions. (Each of the reactants and products in these reactions are gases.)
(1) Chlorine atoms react with ozone (O3) to form chlorine monoxide and molecular oxygen.
(2) Chlorine monoxide forms ClOOCl.
(3) ClOOCl absorbs sunlight and breaks into chlorine atoms and molecular oxygen. If the coefficient for a particular substance is "1", do not write the "1" in the balanced equation. For example, instead of writing "1Cl(g)", simply write "Cl(g)".
(a) Write a balanced equation for each step, including the state of each molecule.
(b) Write an overall balanced equation for the sequence.
Ozone O₃ consists of a strong reactive gas made up of three atoms of oxygen. Ozone occurs on the Earth as natural and man-made gas.
Ozone impacts life on Earth in positive or harmful ways depending upon its location in the atmosphere.
From the information given, we are to balance the reactant and the product that leads to the formation of Ozone by following each step.
Step 1:
2Cl° + 2O₃ 2ClO° + 2O₂
Chlorine molecular
monooxide oxygen
Step 2:
2ClO° ClOOCl
Step 3:
ClOOCl + sunlight → 2Cl° + O₂
(b)
The Overall balanced equation can be expressed as:
2O₃ → 3O₂
Therefore, from the above explanation we can see the step by step process for the balanced equation and the overall balanced equation.
Learn more about balancing equation here:
https://brainly.com/question/7181548?referrer=searchResults
What would most likely happen if the kangaroo rats
were killed off and removed from the food chain?
Answer:
Explanation:
The number of cactus plants would increase.
Illustrate the law of law of multiple proportions using the formation of SO2 and SO3 by sulphur and oxygen
As illustrated from law of multiple proportion, the mass of the oxygen which combined with a fixed mass of the sulphur is in simple whole number ratio of 2 is to 3 (2:3).
The law of Multiple proportion states that when two elements combine to form more than one compound, the mass of the second element, which combines with a fixed mass of the first element, will always be ratios of small whole numbers.
To illustrate the law of multiple proportion from sulphur and oxygen, we use the given compounds.
The reaction of oxygen with sulphur to form SO₂ and SO₃:
[tex]S \ + \ O_2 \ -----> SO_2\\\\2SO_2 \ + \ O_2 \ ---> \ 2SO_3[/tex]
atomic mass of oxygen = 16 g
atomic mass of sulphur = 32 g
In the formation of SO₂:mass of sulphur = 32 g and mass of oxygen = (2x16) = 32 g
In the formation of SO₃:mass of sulphur = 32 g and mass of oxygen = (3 x 16) = 48 g
Notice, while mass of sulphur is constant, mass of oxygen changed.
The ratio of mass of oxygen in the given two compounds = 32g : 48g = 2:3
Thus, based on the law of multiple proportion, the mass of the oxygen which combined with a fixed mass of the sulphur is in simple whole number ratio of 2 is to 3 (2:3).
Learn more here: https://brainly.com/question/15537778
the internacional system of units is based on ?
Answer:
The international system of units is basic on 7 units.
Hope it helps you.Neha and Reha are playing see-saw. Neha is sitting 60 cm away from the fulcrum and Reha is sitting 40 cm away from the fulcrum. Calculate the effort that Reha should apply to lift Neha. The weight of Neha is 360 N.
Answer:
Reha should apply 540 N to lift Neha.
Explanation:
L = 360 N
LD = 60 m
E =?
ED = 40m
NOW
L * LD = E * ED
360 *60 = E*40
21600/40 = E
540 N = E
A graduated cylinder is filled with 20ml of water. A rock is dropped in to the graduated cyclinder and the volume of water rises to 30ml
inside the graduated cylinder. The mass of the rock is 23g. What is the density of the rock?
2.3g/ml
0.77g/ml
5g/ml
1.15g/ml
Answer:
[tex]\boxed {\boxed {\sf 2.3 \ g/mL}}[/tex]
Explanation:
We are asked to find the density of a rock. Density is the substance's mass per unit volume. The formula for calculating density is:
[tex]\rho= \frac{m}{v}[/tex]
The mass of the rock is 23 grams. The volume was found using water displacement. A known amount of water was measured, the rock was added to the graduated cylinder, and the water level was recorded again. The volume is the difference between the final and initial water level. The graduated cylinder originally had 20 milliliters and the water rose to 30 milliliters.
volume = final water level - initial water level volume = 30 mL - 20 mLvolume = 10 mLNow we know the mass and the volume.
m= 23 g v= 10 mLSubstitute the values into the formula.
[tex]\rho= \frac{ 23 \ g }{30 \ mL}[/tex]
Divide.
[tex]\rho= 2.3 \ g/mL[/tex]
The density of the rock is 2.3 grams per milliliter.
What kinds of questions cannot be answered by chemistry
why does copper Cu (I) have a short lifespan
Answer:
Copper (Cu), chemical element, a reddish, extremely ductile metal of Group 11 (Ib) of the periodic table that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature.
Explanation:
hope this helps:)
In nature, Chlorine-35 isotopes (35 amu) make up 75
% of all chlorine. Chlorine-37 (37 amu) isotopes make
up 25 % of all chlorine,
Show your calculation for the AVG. Atomic Mass of
chlorine:
identify 2 ways to measure mass
Answer:
The two ways to measure mass are subtraction and taring.
Help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
bubble and foam!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
3. If we remember seeing something happen, we can trust that it happened just as we think it did. True or False
[tex] \huge{ \underbrace{ \overbrace{True}}}[/tex]
.
[tex]\huge\mathfrak\purple{Hope \: it \: helps}[/tex]
Note : Because Many of My Dreams came true and I realized.
11) Calcium Chloride, CaCl2, can be used instead of road salt to melt the ice on roads during the winter. To determine how much calcium chloride had been used on a nearby road, a student took a sample of slush to analyze. The sample had a mass of 23.47g. When the solution was evaporated, the residue had a mass of 4.58g (assume that no other solutes were present).
a) What was the mass/mass percent of calcium chloride in the slush
b) How many grams of calcium chloride were present in 100g solution?
Answer:
What is that? I do not understand
Which pair of reactants for a Grignard reaction does not give 2-phenylbutan-2-ol after an aqueous workup?
what is seed reproduction
Answer:
A seed is formed when fertilised ovule divides by mitosis. ... The ovary of the flower develops into the fruit while ovules develop into seeds. The formation of seed completes the process of reproduction in plants. Within the seed, the growing embryo develops and matures.
I hopes it helps you.3(b) The balloon did not burst when it is pressed onto 100 nails because
1. the nails are not sharp
2.the surface area of 100 nails produce high pressure on the balloon
3. the larger surface area of 100 nails produce low pressure on the balloon
3(c) To reduce pressure on the contact surface, we must apply force onto the .................... surface area.
1.largest
2.smallest
3. Any size of
What is a mixture? How will you separate the components of a mixture containing sugar, sand and water?
Answer:
Mixture is combination of two or more substances
Explanation:
The sugar would dissolve in water. You could then pour off the solution and wash the remaining sand with a bit more water. Heat the water to evaporate it from the sugar, and the two are separated.
calculate the number of each atom in 2.5 gram of caco3
Answer:
[tex]2.5\; \rm g[/tex] of [tex]\rm CaCO_{3}[/tex] would contain:
Approximately [tex]1.5 \times 10^{22}[/tex] calcium atoms (approximately [tex]0.025\; \rm mol[/tex],)Approximately [tex]1.5 \times 10^{22}[/tex] carbon atoms (approximately [tex]0.025\; \rm mol[/tex],) andApproximately [tex]4.5 \times 10^{22}[/tex] oxygen atoms (approximately [tex]0.075\; \rm mol[/tex].)Explanation:
Look up the Avogadro constant: [tex]N_{\rm A} \approx 6.022 \times 10^{23}\; \rm mol^{-1}[/tex].
For example, "[tex]1\; \rm mol[/tex] of carbon atoms" would contain [tex]N_{\rm A}[/tex] carbon atoms (approximately [tex]6.022\times 10^{23}[/tex]) by definition.
Look up the relative atomic mass of carbon, calcium, and oxygen on a modern periodic table:
Calcium: [tex]40.078[/tex].Carbon: [tex]12.011[/tex].Oxygen: [tex]15.999[/tex].In other words, the mass of [tex]1\; \rm mol[/tex] of calcium atoms would be [tex]40.078\; \rm g[/tex]. The mass of [tex]1\; \rm mol\![/tex] of carbon atoms would be [tex]12.011\; \rm g[/tex], and the mass of [tex]1\; \rm mol \!\![/tex] of oxygen atoms would be [tex]15.999\; \rm g[/tex].
As the formula [tex]\rm CaCO_{3}[/tex] suggests, every formula unit of this ionic compound includes one calcium atom, one carbon atom, and three oxygen atoms. The formula mass of [tex]\rm CaCO_{3}\![/tex] would give the mass of every mole of [tex]\rm CaCO_{3}\!\![/tex] formula units.
Calculate the formula mass of [tex]\rm CaCO_{3}[/tex] from the relative atomic mass data:
[tex]\begin{aligned} & M({\rm CaCO_{3}}) \\ =\; & 40.078\; \rm g \cdot mol^{-1} \\ & + 12.011\; \rm g \cdot mol^{-1} \\ & + 3 \times (15.999\; \rm g \cdot mol^{-1}) \\ =\; & 100.086\; \rm g \cdot mol^{-1}\end{aligned}[/tex].
Calculate the number of [tex]\rm CaCO_{3}[/tex] formula units in that [tex]2.5\; \rm g[/tex] of this compound:
[tex]\begin{aligned}& n({\rm CaCO_{3}}) \\ =\; & \frac{m({\rm CaCO_{3}})}{M({\rm CaCO_{3}})} \\ =\; & \frac{2.5\; \rm g}{100.086\; \rm g \cdot mol^{-1}} \\ \approx\; & 0.025\; \rm mol\end{aligned}[/tex].
In other words, [tex]2.5\; \rm g[/tex] of [tex]\rm CaCO_{3}[/tex] would contain approximately [tex]0.025\; \rm mol[/tex] [tex]\rm CaCO_{3}\![/tex] formula units.
Again, there are one calcium atom, one carbon atom, and one oxygen atom in every [tex]\rm CaCO_{3}[/tex] formula unit. That approximately [tex]0.025\; \rm mol[/tex] [tex]\rm CaCO_{3}\![/tex] formula units would thus contain:
Approximately [tex]1 \times 0.025\; \rm mol = 0.025\; \rm mol[/tex] calcium atoms, Approximately [tex]1 \times 0.025\; \rm mol = 0.025\; \rm mol[/tex] carbon atoms, andApproximately [tex]3 \times 0.025\; \rm mol = 0.075\; \rm mol[/tex] oxygen atoms.Make use of the Avogadro constant to convert the numbers.
For example, the number of calcium atoms in that approximately [tex]0.025\; \rm mol[/tex] of calcium atoms would be:
[tex]\begin{aligned} & N({\text{calcium}) \\ = \; & n({\text{calcium}) \cdot N_{\rm A} \\ \approx \; & 0.025\; \rm mol \times 6.022\times 10^{23} \cdot mol^{-1} \\ \approx \; & 1.5 \times 10^{22} \end{aligned}[/tex].
Likewise, the number of carbon atoms in that approximately [tex]0.025\; \rm mol[/tex] of carbon atoms would be:
[tex]\begin{aligned} & N({\text{carbon}) \\ = \; & n({\text{carbon}) \cdot N_{\rm A} \\ \approx \; & 0.025\; \rm mol \times 6.022\times 10^{23} \cdot mol^{-1} \\ \approx \; & 1.5 \times 10^{22} \end{aligned}[/tex].
The number of oxygen atoms in that approximately [tex]0.075\; \rm mol[/tex] of oxygen atoms would be:
[tex]\begin{aligned} & N({\text{oxygen}) \\ = \; & n({\text{oxygen}) \cdot N_{\rm A} \\ \approx \; & 0.075\; \rm mol \times 6.022\times 10^{23} \cdot mol^{-1} \\ \approx \; & 4.5 \times 10^{22} \end{aligned}[/tex].
If you wanted to increase the speed of
vaporization, you could
A. put the substance in the freezer.
B. place a lid on the substance.
C. heat the substance to the boiling point.
D. cool the substance to the freezing point.
>
Copyright © 2003 - 2021 Acellus Corporation. All Rights Reserved.
Answer:
C. heat the substance to the boiling point.
Answer:
heat the substance
Explanation:
what is x if x - 2 =0
Answer:
x-2 = 0
x = 2
hope this was help full
4. In KCl, how are the valence electrons distributed?
O A. The electrons are shared between many K and Cl ions, creating a "sea of electrons."
B. The electrons are transferred from K to CI.
O c. The electrons are equally shared between K and Cl, forming a covalent bond.
D. The electrons are unequally shared between K and Cl, forming a polar covalent bond.
Answer:
Since KCl is an ionic compound, there is transfer of electrons from K to Cl. Thus right answer should be (B)
KCl is a chemical called potassium chloride that has been known to be an ionic compound. The valence electrons ion KCl gets transferred from K to Cl ion. Thus, option B is correct.
What is an ionic bond?An ionic bond is said to be a type of chemical bond that involves the gain and loss of the electron in the valence shell of the atom species. It involves the bond formation between the ions.
The ions with opposite charges, carrying a positive and negative are said to bond by accepting and donating their electrons to achieve the noble-gas (electronic) configuration.
In KCl, potassium has more electrons and can donate it to chlorine species as the latter lacks electrons. Chlorine accepts electrons and in the process acquires a negative charge, whereas potassium gains a positive charge.
Therefore, option B. the KCl involves ionic bonds by transferring electrons.
Learn more about ionic bonds, here:
https://brainly.com/question/6995576
#SPJ2
What is the final temperature of water given an initial temperature of 28 ˚C, a mass of 7 g, and heat (q) of 184 J (Specific Heat of water = 4.184 )?
Answer:34.28 Degree celcius
Explanation:The heat given is equal to the change in temperature multiplied by the mass and the specific heat capacity
This gives the equation:Q=mc∆T
Where Q=184,m=7, specific heat capacity=4.184,∆T=X-28,
But ∆T=Final temperature (T'')-Initial temperature (T')
Therefore the equation becomes
184=7×4.184(X-28)
Solving the remaining linear equation gives you X as 34.28°C
