Answer:
The Answer is 2.1
Hope this helps!
How many electrons does an atom have if the mass number is 31 and the number of neutrons is 16?
Answer:
I'm pretty sure it's 15 electrons. Hope this helps :).
Explanation:
The temperature of 25 g of water was raised from 10 oC to 60 oC. How many joules of heat was necessary to accomplish this?
Answer:
Hope this helps!
Explanation:
what information does a chemical equation contain
Answer:
Chemicals should involve information about properties and reactants.
answer with correct significant figures (*no scientific notation): 847.3219 x 34.6 x 1.4560 =
Answer:
42686.04375
Explanation:
Multiply 847.3219 by 34.6 to get 29317.33774, then multiply this answer by 1.4560 to get the final answer which is 4286.04375.
Can someone please help me and explain how to do this :')
How many moles of O₂ are needed to produce 3.17 mol of carbon monoxide from it's elements by a synthesis reaction?
Answer:
this is the answer explanation of previous question. as what you say in comment i do that
ine element and compound with example.
What is symbol? Write its significance.
Define mixture. Write its types.
Write the difference between mixture and compound.
What is a chemical equation? What are the essentials of
chemical equation? What information is conveyed by
chemical equation? What are its limitations and how are they
removed?
What do you understand by balancing of a chemical equation
Why 'partial equation method' is considered to be better than
"hit and trial method'?
What information is
Explanation:
an element is a substance which cannot be spilt upto two or more simple substances.For eg gold,silvera compound is the substance produced by the union of two or more elements in a definite proportion by weight .For eg water,carbon dioxideI dont knowA mixture is a substance formed by mixing two or more elements are compounds in any proportion by mass .Its types are:Hetregeneous mixture and homogeneous mixture.the difference between mixture and compound is that a mixture is a substance formed by mixing two or more elements are compounds in any proportion by maths and compound is a substance produced by the union of two or more elements in a definite proportion by weight.chemical equation is defined as the symbolic representation of a chemical reactionAbout Salva Chapter 14
1.Why isn’t Nya happy when the borehole water starts flowing?
2.How much time has now passed since Salva fled from his school?
3.What was life like in the Kakuma and Ifo refugee camps?How did they compare?
4.What does Salva mean when he thinks,”It was hard to keep hope alive when there was so little to feed it?”
5.Where does Salva finally find this hope?
Answer:
Because it is muddy and dirty.9 yearsDreadful / Compared The Ifo and Kakuma camps: Isolated areasThere was no way Salva could ever reach his goal of branching out into the world if he was stuck at the camp.When he hears that 3000 boys will be chosen to go to America.Anna is conducting an experiment to determine how weather affects cell phone reception. She is trying to decide the best way to conduct her experiment in order to collect meaningful data.
The question is incomplete, the complete question is;
Anna is conducting an experiment to determine how weather affects cell phone reception. She is trying to decide the best way to conduct her experiment in order to collect meaningful data. Which of the following experiments would help Anna collect the best data? A. Test different cell phones in different locations on days with clear weather. B. Test different cell phones in different locations on days with rainy weather. C. Test a cell phone's reception in one location with clear weather and in another location with rainy weather. D. Test a cell phone's reception in the exact same location under various atmospheric conditions.
Answer:
D. Test a cell phone's reception in the exact same location under various atmospheric conditions.
Explanation:
In this experiment that Anna intends to carry out, the independent variable is the atmospheric condition. The dependent variable must be the cell phone reception, it is expected to change with atmospheric conditions.
In order to obtain valid results, other factors such as such as type of cellphone and location (control variables) must be held constant so as to collect the best data.
Write out the chemical equations showing how a buffer solution made from H2PO4- and HPO42- would react to the addition of an acid (H+ ions) or a base (OH- ions).
Answer:
kindly check the explanation section.
Explanation:
The two ions given in the question above that is Dihydrogenphosphate, H2PO4- and HPO42- are so important when it concerns buffering. During intracellular pH balancing the ions that is H2PO4- and HPO42- reacts with OH⁻ and H⁺ respectively. The equation for the chemical reaction is given below for both ions.
H₂PO₄⁻ + OH⁻ < =====================================> HPO₄²⁻ + H₂O.
HPO₄²⁻ + H⁺ <===========================================> H₂PO₄⁻.
The number of molecules in 48.0 grams of oxygen gas (O2) is...
O 6.02 x 1023
O 1.81 x 1024
O 1.20 x 1024
9.03 x 1023
Answer:
9.033 × 10²³ molecules
Explanation:
Given data:
Mass of oxygen = 48.0 g
Number of molecules = ?
Solution:
Number of moles of oxygen:
Number of moles = mass/molar mass
Number of moles = 48.0 g/ 32 g/mol
Number of moles = 1.5 mol
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
1.5 mol × 6.022 × 10²³ molecules / 1mol
9.033 × 10²³ molecules
Based only on the distance between the valence electron and the nucleus, which atom has a stronger attraction between its nucleus and its valence electrons? How do you know? Please explain in at least 2 sentences.
lithium and sodium
Answer:
Lithium
Explanation:
Although sodium may seem like a viable answer because it has more protons (and thus a greater attractive force) in its nucleus, we need to take into account what "valence electrons" means. Valence electrons are, simply, electrons that are on the outermost electron shell of an atom. Sodium has an additional shell of electrons compared to lithium that are far away from the nucleus. Thus, lithium, which has valence electrons closer to its nucleus, would have a stronger attraction between its nucleus and its valence electrons.
Na2S2O3 + AgBr NaBr + Na3ſAg(S203)2] What is
the mass of NaBr that will be produced from 42.7 g of AgBr?
Answer:
Mass of NaBr produced = 23.67 g
Explanation:
Given data:
Mass of AgBr = 42.7 g
Mass of NaBr produced = ?
Solution:
Chemical equation:
2Na₂S₂O₃ + AgBr → NaBr + Na₃(Ag(S₂O₃)₂
Number of moles of AgBr:
Number of moles = mass/molar mass
Number of moles = 42.7 g/ 187.7 g/mol
Number of moles = 0.23 mol
now we will compare the moles of AgBr with NaBr.
AgBr : NaBr
1 : 1
0.23 : 0.23
Mass of NaBr:
Mass = number of moles × molar mass
Mass = 0.23 mol × 102.89 g/mol
Mass = 23.67 g
Describe two ways the material in illustrates the importance of creativity in scientific investigations
Answer:
J.J Thompson make use of creativity to explain cathode ray tube experiment.
Also, creativity was used by Daltons to explain Joseph Proust's work.
Explanation:
This problem is all about the the beginning part of chemistry that is the atomic theory. The atomic theory was starts from the time of people like Democritus and down to people like J.J Thompson and John Dalton. Although it has been registered and credited that Dalton is the father of atomic theory many people has also worked on it before him for instance person like Joseph Proust. The reason behind this because some works that has been done by other people such as Democritus[who was the first person to start atomic studies] does not have any scientific evidence.
Creativity is needed when it concerns scientific research and investigation. This is what scientists such as John Daltons and J.J Thompson have used. J.J Thompson make use of creativity to explain cathode ray tube experiment. Also, creativity was used by Daltons to explain Joseph Proust's work.
Which of the following is true about nuclear fusion
a) it occurs in the sun
b) a heavy atom is split
c) it can be controlled easily
d) an electron is lost by the atom
Answer:
i would assume that it would be (a)
Explanation:
The Sun generates its energy by nuclear fusion
NUCLEAR FISSION is when the heavy atom is split
fusion energy is scientifically feasible. Plasma conditions that are very close to those required in a fusion reactor are now routinely reached in experiments
mass gets lost is nuclear fusion
so (a) is the most accurate
Answer:
it occurs in the sun
Explanation:
just took the test so its A. GL!
What happens to brain cells when we sleep?
Answer:
What happens is...
Explanation:
Specifically, it allows your neurons, or nerve cells, to reorganize. When you sleep, your brain's glymphatic (waste clearance) system clears out waste from the central nervous system. It removes toxic byproducts from your brain, which build up throughout the day. This allows your brain to work well when you wake up.
If hydrochloric acid has a [H+] of 1.2 x 10-2 M, what is the pH?
1.9
0 1
1.2
O
8
Answer:
1.9Explanation:
The pH of a solution can be found by using the formula
[tex]pH = - log [ {H}^{+} ][/tex]
From the question we have
[tex]pH = - log(1.2 \times {10}^{ - 2} ) \\ = 1.920818...[/tex]
We have the final answer as
1.9Hope this helps you
Answer:
1.9
Explanation:
9.
How would your mass and weight differ on the moon? (The gravitational force on the
moon is 1/6 the force on Earth).-
Answer: Your mass would be the same, but you would weigh less because the gravity on the moon is less than it is on Earth.
Explanation:
balance the following skeleton equations Mg+02---->MgO
Answer: [tex]2Mg+O_2\rightarrow 2MgO[/tex]
Explanation:
Skeletal equations are defined as the equations in which formula are used to indicate the chemicals that are involved in a chemical reaction.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Thus the balanced chemical equation will be :
[tex]2Mg+O_2\rightarrow 2MgO[/tex]
List six elements with only 1 electron in an s orbital
Answer:
[tex]Lithium=Li2s^1\\Sodium=Na3s^1\\Potassium=K4s^1\\Rubidium=Rb5s^1\\Cesium=Cs6s^1\\Francium=Fr7s^1[/tex]
Explanation:
When it comes to electron configuration and orbitals, it's important to first identify what exactly we are trying to identify. Below is a given example:
[tex]He1s^2[/tex]
[tex]He=element[/tex]
[tex]1=level[/tex]
[tex]s=orbital[/tex]
[tex](exponent)^2=electrons[/tex]
Looking at the periodic table, identify the alkali metal family on the periodic table, or group one elements:
[tex]Lithium=Li2s^1\\Sodium=Na3s^1\\Potassium=K4s^1\\Rubidium=Rb5s^1\\Cesium=Cs6s^1\\Francium=Fr7s^1[/tex]
Notice how each configuration has an exponent of [tex]1[/tex], representative of a single electron in their s-orbital.
PLEASEEE HELP me on CHEMISTRY!! Will give brainliest!
Two students plan and carry out an investigation to determine if ionic or covalent bonds have stronger intermolecular forces. They check the following data.
a. identify the type of intramolecular bonds that are involved.
b. Which substance will have the stronger intermolecular forces?
c. Which properties allow you to predict the strength of the intermolecular forces?
Answer:
A Glucose C6H12O6 is a covalent compound while NaCl sodium chloride is a ionic compound.
B Stronger molecular forces are present in NaCl because ionic bond is stronger than covalent bond.
C melting point allow us to predict the strength of intermolecular forces
High melting point stronger molecular forces and vice versa.
Explanation:
the Central value of the set of observation is called.
Answer:
The central value of the sets of observation can be mean, median or mode depending upon the kind of data provided as all are measure of central tendency.
Explanation:
According to Valence Shell Electron Pair Repulsion (VSEPR) theory, which statement is correct? If a molecule has four pairs of electrons, it will always have a tetrahedral structure. If a molecule is made up of three atoms, it will always have a linear structure. If a molecule is bent, it will always have unpaired electrons around the central atom. If a molecule has three atoms around a central atom, it will always be trigonal planar.
Answer: Option 1
Explanation: hopes it helps
Valence Shell Electron Pair Repulsion (VSEPR) theory is employed in prophesying the geometrical organisation of the specific molecule with the aid of electron sets found encompassing the atom.
The correct answer is:
Option A. If a molecule has four pairs of electrons, it will always have a tetrahedral structure.
This can be explained as:
To reduce the electron repellence atom having four pairs of electrons will always accommodate to a tetrahedral structure.An atom comprising four pairs of electrons will have no lone pairs and hence, tetrahedral geometry.An example of tetrahedral geometry is methane (CH4).Therefore atom containing four pairs of electrons will have a tetrahedral shape.
To learn more about VSEPR theory follow the link:
https://brainly.com/question/12775505
is methane used as fule
gas true or false
Answer:
its true methane is used as a fuel gas
Explanation:
the term pH was discovered by which scientist
Answer:
Such was the case with the concept of pH, introduced in 1909 by Søren Sørensen as a convenient way of expressing acidity—the negative logarithm of hydrogen ion concentration.Jan 8, 2018
Profession: Chemist
A student was tasked with experimentally determining the mole ratio of strontium chlorate hexahydrate. The students data follows below. Determine the experimental molar ratio for strontium chlorate hexahydrate to proper significant figures (4) based on the data below. Calculate the students percent error.
Mass of clean dry crucible – 21.05 g
mass of crucible and sample – 23.36 g
mass of crucible & sample after heating – 22.49 g
Compare and contrast a thermodynamically stable compound and a kinetically stable compound at room temperature with respect to overall energy change, spontaneity with which decomposition occurs, and reaction rate.
Answer:
"im different"
Explanation:
This chemical equation represents a chemical reaction.
Na2CO3 + 2HCl - 2NaCl + CO2 + H20
Which chemical is a reactant in the reaction shown?
A. HCI
B. NaCl
C. CO2
D. H20
Answer:
A. HCl
Explanation:
on the left hand side we have reactants.
hope it helps!
At which point is kinetic energy greatest
Answer:
x is wen
Explanation:
Answer:
I would say at point ''X''
help me pleaseeee, ty if you doo :))
The reaction energy type that has a negative value at the end of the reaction is called: a Barothermic b Exothermic c Endothermic d Isothermic
Answer:
b) Exothermic
Explanation:
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol