Answer:
A. 1.377 g
B. 16.5%
Explanation:
To find the water loss, subtract the salt and crucible mass from the hydrate and crucible mass
21.018 - 19.641 = 1.377
To find the water mass percentage, divide the empty crucible mass by the mass of the hydrate and crucible. Then, subtract that number from 1.
17.556 ÷ 21.018 = 0.835284
1 - 0.835284 = 0.164716
If you want to add an extra step, multiply this number by 100 to get the percentage.
0.164716 x 100 = 16.4716
How did Kepler's discoveries contribute to astronomy?
O They supported the heliocentric model.
O They established the laws of planetary motion.
O They explained how the Sun rises and sets.
O They made astronomy accessible to people who spoke Italian.
They made astronomy accessible to people who spoke italian
Answer:
"They established the laws of planetary motion"
Explanation:
Mr. Kepler was the astronomer who came up with the "Laws of Planetary Motion."
A central atom has two lone pairs on opposite sides and four single bonds. What is the molecule geometry of the result?
A. octahedral
B. tetrahedral
C. square planar
D. linear
The correct answer is C. square planar
According to the Valence Shell Electron Pair Repulsion Theory(VSEPR), The shape of a molecule depends on the number of electron pairs in the molecule.
VSEPR theory was first coined by Gillespie and Nyhlom in 1957 as an improvement over the Sidgwick - Powell theory.
According to this theory, the shape of a molecule is determined by the number of electron pairs that surround the valence shell of the central atom in the molecule. The electron pairs are positioned as far apart in space as possible to minimize repulsion of electron pairs.
However, the presence of lone pairs distorts the shape anticipated for the molecule on the basis of VSEPR.
For a molecule having six electron pairs, an octahedral geometry is expected(electron domain geometry). However, the presence of two lone pairs which are positioned at opposite side of the four single bonds leads to an observed square planar molecular geometry.
https://brainly.com/question/13591921
Answer:
square planar
Explanation:
In the graphic, 195 represents the _______.
195 Pt
78
A. Atomic Mass
B. Atomic Number
C. Neutron Number
Answer:
ITS ANSWER IS
OPTION B. ATOMIC NUMBER
HI HAVE A NICE DAY
. Which of the following statement is not related to a chemical reaction ? A. New substances are formed B. Atoms of the elements transform into atoms of other elements C. The properties of the new substances will be different D. There will be bond breaking and bond forming
Answer:
the answer should be B because elements do not tranform into other elements in a chemical reaction
am I right please?
Sometimes the oxidation state of an analyte must be adjusted before it can be titrated.
a. True
b. False
Answer:
Explanation:
True
When water reaches the metastable state, the phase of water will be?
Answer:
water, when the metastable state is reached, is cooled below the zero temperature. It freezes abruptly. this is called metastable. They are not at equilibrium per se; as at negative temperatures the only equilibrium state of water is ice.
Explanation:
Which substance will sublimate when in the solid phase at room temperature and pressure?
Select the correct answer below:
A) carbon dioxide
B) water
C) mercury
D) helium
Answer:
I think carbon dioxide is right answer
What volume of each solution contains 0.14 mol of KCl? Express your answer using two significant figures.
1.8 M KCl
Answer:
Solution given:
1 mole of KCl[tex]\rightarrow [/tex]22.4l
1 mole of KCl[tex]\rightarrow [/tex]74.55g
we have
0.14 mole of KCl[tex]\rightarrow [/tex]74.55*0.14=10.347g
74.55g of KCl[tex]\rightarrow [/tex]22.4l
10.347 g of KCl[tex]\rightarrow [/tex]22.4/74.55*10.347=3.11litre
volume of each solution contains 0.14 mol of KCl contain 3.11litre.
1 mol of any gas contains 22.4L of volume at STP
Moles of KCl=0.14Volume of KCl:-
0.14(22.4)3.14LA natural element consists of two isotopes: Cl-35 and Cl-37. The composition of these two isotopes differs by:
Answer:
There are no options in this question, however, it can be answered based on general understanding
- The number of neutrons each isotope contain
Explanation:
Isotopes are atoms of an element with the same atomic number or number of protons but different mass number/atomic masses. Since isotopes have same proton numbers, they have similar chemical behavior or identity.
However, difference in atomic mass or mass number of the same atomic number indicates that the number of neutrons each isotope contain differs from one another. Hence, in two isotopes of chlorine given as follows: Cl-35 and Cl-37, the NUMBER OF NEUTRONS in each atom differentiates the two isotopes.
Cl-35 contains 18 neutrons while Cl-37 contains 20 neutrons.
What is the difference between the chemical formula of water and carbon dioxide?
The chemical formula of water is H2O, and the chemical formula of carbon dioxide is CO2. This means that water has 2 atoms of hydrogen and 1 atom of oxygen, which carbon dioxide has 1 atom of carbon and 2 atoms of oxygen. The only similar atom that the two molecules have in common is oxygen. CO2 has one more atom of oxygen than H2O. Hope this helps!
H2O is water. CO2 is CD.
Define pressure. Group of answer choices force exerted by solids to the surrounding area force used to compress a gas force used to melt a solid force exerted per unit area by gas particles as they strike the surfaces around them force applied to a gas to condense it
Answer:
force exerted per unit area by gas particles as they strike the surfaces around them
Explanation:
According to the kinetic molecular theory, a gas is composed of molecules. The molecules of a gas are in constant random motion and collide frequently with each other as well as with the walls of the container.
Pressure is defined as force per unit area. The pressure of a gas is the force exerted per unit area by gas particles as they strike the surfaces around them hence the answer above.
China is the leading producer of
Answer:
Production of some products is highly concentrated in a few countries, China, the leading producer of wheat and ramie in 2013, produces 6% of the world's ramie fiber but only 17% of the world's wheat.
A s'more requires 2 graham cracker squares, 1 marshmallow, and 3 chocolate pieces. If an entire chocolate bar contains 12 chocolate pieces, a marshmallow bag contains 40 marshmallows, and a graham cracker package contains 48 squares, how many s'mores can you make from 8 chocolate bars, one bag of marshmallows, and a package of graham crackers?
Explanation:
try 96 if that's not right let me know and I'll try to fix it
Answer:24
Explanation:
A chunk of a metal alloy displaces 0.58 L of water and has a mass of 2.9 kg. What is the density of the alloy in g/cm3?
Answer:
5g/cm3
Explanation:
firstly convert the litres and kilograms to grams and centimeters.
1l is equivalent to 1000cm3
0.58×1000
580cm3
and 1kg is equivalent to 1000g
2.9×1000
2900
then find the density by using the formula
density=mass/volume
=2900g/580cm3
=5g/cm3
I hope this helps
Select all that are True.
a. For an isoelectronic series, the species with the most negative charge has the smallest first ionization energy.
b. The removal of an electron from a neutral atom results in a release of energy in the form of heat.
c. For an isoelectronic series, the species with the most positive charge has the smallest first ionization energy.
Which of the following statements is true about what happens in all chemical reactions? A. The ways in which atoms are joined together is not changed. B. Bonds between atoms are broken and new bonds are formed. C. The final substances are called reactants.
Answer:
B.bonds are broken and new bonds are formed
the probability that it will rain tomorrow is 11/15. What is the probability that it will not rain ?
Answer:
4/15
Explanation:
15/15 - 11/15 = 4/15
If 11/15 is the probability that it'll rain tomorrow, then the rest should be the probability that it'll not rain tomorrow.
PLEASE HELP!!
this is on USAtestprep
a)
b)
c)
d)
Answer:
B
Explanation:
the fluorine has an high tendency to gain electrons from other elements with lower electronegativities
How many moles of iron is equivalent to 4.45 x 10^22 atoms of iron
Answer:
0.074 moles
Explanation:
For every mole (of any element), there are 6.022 x 10^23 atoms.
There are 4.45 x 10^22 atoms of iron.
To find the moles we divide the number of atoms by Avogadro's number
4.45 x 10^22 / 6.022 x 10^23 = 0.0738957
Don't forget sig figs
Answer:
[tex]\boxed {\boxed {\sf 0.0739 \ mol \ Fe}}[/tex]
Explanation:
We are asked to convert a number of iron atoms to moles of iron.
We will use Avogadro's Number for this, which is 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units, etc.) in 1 mole of a substance. For this problem, the particles are atoms of iron. There are 6.022 ×10²³ atoms of iron in 1 mole of iron.
We will also use dimensional analysis to solve this problem. To do this, we use ratios. Set up a ratio using the underlined information.
[tex]\frac {6.022 \times 10^{23} \ atoms \ Fe} {1 \ mol \ Fe}[/tex]
Since we are converting 4.45 × 10²² atoms of iron to moles, we multiply the ratio by that value.
[tex]4.45 \ \times 10^{22} \ atoms \ Fe *\frac {6.022 \times 10^{23} \ atoms \ Fe} {1 \ mol \ Fe}[/tex]
Flip the ratio. The value is the same, but it allows us to cancel the units of atoms of iron.
[tex]4.45 \ \times 10^{22} \ atoms \ Fe *\frac {1 \ mol \ Fe}{6.022 \times 10^{23} \ atoms \ Fe}[/tex]
[tex]4.45 \ \times 10^{22} *\frac {1 \ mol \ Fe}{6.022 \times 10^{23}}[/tex]
Condense into 1 fraction.
[tex]\frac {4.45 \ \times 10^{22} }{6.022 \times 10^{23}} \ mol \ Fe[/tex]
[tex]0.07389571571 \ mol \ Fe[/tex]
The original measurement of atoms ( 4.45 × 10²²) has 3 significaint figures, so our answer must have the same. For the number we calculated, that is the ten-thousandths place. The 9 to the right of this place (0.07389571571) tells us to round the 8 up to a 9.
[tex]0.0739 \ mol \ Fe[/tex]
There are approximately 0.0739 moles of iron in 4.45 × 10²² atoms of iron.
150 mL of 0.25 mol/L magnesium chloride solution and 150 mL of 0.35 mol/L silver nitrate solution are mixed together. After reaction is completed; calculate the concentration of nitrate ions in solution. Assume that the total volume of the solution is 3.0 x 10^2 mL
Answer:
[tex]0.175\; \rm mol \cdot L^{-1}[/tex].
Explanation:
Magnesium chloride and silver nitrate reacts at a [tex]2:1[/tex] ratio:
[tex]\rm MgCl_2\, (aq) + 2\, AgNO_3\, (aq) \to Mg(NO_3)_2 \, (aq) + 2\, AgCl\, (s)[/tex].
In reality, the nitrate ion from silver nitrate did not take part in this reaction at all. Consider the ionic equation for this very reaction:
[tex]\begin{aligned}& \rm Mg^{2+} + 2\, Cl^{-} + 2\, Ag^{+} + 2\, {NO_3}^{-} \\&\to \rm Mg^{2+} + 2\, {NO_3}^{-} + 2\, AgCl\, (s)\end{aligned}[/tex].
The precipitate silver chloride [tex]\rm AgCl[/tex] is insoluble in water and barely ionizes. Hence, [tex]\rm AgCl\![/tex] isn't rewritten as ions.
Net ionic equation:
[tex]\begin{aligned}& \rm Ag^{+} + Cl^{-} \to AgCl\, (s)\end{aligned}[/tex].
Calculate the initial quantity of nitrate ions in the mixture.
[tex]\begin{aligned}n(\text{initial}) &= c(\text{initial}) \cdot V(\text{initial}) \\ &= 0.25\; \rm mol \cdot L^{-1} \times 0.150\; \rm L \\ &= 0.0375\; \rm mol \end{aligned}[/tex].
Since nitrate ions [tex]\rm {NO_3}^{-}[/tex] do not take part in any reaction in this mixture, the quantity of this ion would stay the same.
[tex]n(\text{final}) = n(\text{initial}) = 0.0375\; \rm mol[/tex].
However, the volume of the new solution is twice that of the original nitrate solution. Hence, the concentration of nitrate ions in the new solution would be [tex](1/2)[/tex] of the concentration in the original solution.
[tex]\begin{aligned} c(\text{final}) &= \frac{n(\text{final})}{V(\text{final})} \\ &= \frac{0.0375\; \rm mol}{0.300\; \rm L} = 0.175\; \rm mol \cdot L^{-1}\end{aligned}[/tex].
Which of the following is an example of a physical, rather than a chemical, change?
Answer: The question is not clear
Explanation:
Benzoyl chloride undergoes hydrolysis when heated with water to make benzoic acid. Reaction scheme of benzoyl chloride with water and heat over the arrow, and benzoic acid and hydrochloric acid as products. Calculate the molar mass of the reactant and product. Report molar masses to 1 decimal place.
Answer:
The molar mass of benzoic acid is 122.1 g/mol
The molar mass of hydrochloric acid = 36.5 g/mol
Explanation:
Benzoyl chloride is an organic compound with the molecular formula C₆H₅COCl. It is an acyl chloride since is it an organic derivative of a carboxylic acid. Acyl chlorides have the general molecular formula, R-COCl, where R is a side chain.
The R group of benzoyl chloride is the benzyl group C₆H₅. It reacts with water (hydrolysis) to produce hydrochloric acid and benzoic acid. The equation of the reaction is given below:
C₆H₅COCl + H₂O → C₆H₅CO₂H + HCl
The molar mass of benzoic acid as well as of hydrochloric acid is calculated from the sum of the masses of the atoms of the elements present in the compound thus:
Molar mass of carbon = 12.0107 g
Molar mass of hydrogen = 1.00784 g
Molar mass of oxygen = 15.999 g
Molar mass of chlorine = 35.453 g
Molar mass of benzoic acid, C₆H₅CO₂H containing 7 moles of atoms of carbon, 6 moles of atoms of hydrogen and 2 moles of atoms of oxygen = 7 × 12.0107 + 6 × 1.00784 + 2 × 15.999 = 122.1 g
Therefore, the molar mass of benzoic acid is 122.1 g/mol
Molar mass of hydrochloric acid, HCl, containing 1 mole of atoms of hydrogen and 1 mole of atoms of chlorine = 1 × 1.00784 + 1 × 35.453 = 36.5 g
Therefore, the molar mass of hydrochloric acid = 36.5 g/mol
Describe a NAMED example of a non-equilibrium system with respect to it’s energetic nature and equilibrium status.
Answer:
Non-equilibrium thermodynamics is a branch of thermodynamics that deals with physical systems that are not in thermodynamic equilibrium but can be described in terms of variables (non-equilibrium state variables) that represent an extrapolation of the variables used to specify the system in thermodynamic equilibrium.
Explanation:
Which of the following is a characteristic of a scientific practice?
For a different reaction, the plot of the reciprocal of concentration versus time in seconds was linear with a slope of 0.056 M-1 s -1 . If the initial concentration was 2.2 M, calculate the concentration after 100 seconds. Show your work.
Answer:
[tex]C_t=0.165M[/tex]
Explanation:
From the question we are told that:
Slope [tex]K=0.056 M-1 s -1[/tex]
initial Concentration [tex]C_1=2.2M[/tex]
Time [tex]t=100[/tex]
Generally the equation for Raw law is mathematically given by
[tex]\frac{1}{C}_t=kt+\frac{1}{C}_0[/tex]
[tex]\frac{1}{C}_t=0.056*100+\frac{1}{2.2}_0[/tex]
[tex]C_t=0.165M[/tex]
The second-order reaction is the reaction that depends on the reactants of the first or the second-order reaction. The concentration after 100 seconds will be 0.165 M.
What is the specific rate constant?The specific rate constant (k) of the second-order reaction is given in L/mol/s or per M per s. It is the proportionality constant that gives the relation between the concentration and the rate of the reaction.
Given,
Slope (k)= 0.056 per M per s
Initial concentration of the reactant [tex](\rm C_{1})[/tex] = 2.2 M
Time (t) = 100 seconds
The concentration of the reaction after 100 seconds can be given by,
[tex]\rm \dfrac{1}{C_{t}} = kt + \dfrac{1}{C_{1}}[/tex]
Substitute values in the above equation:
[tex]\begin{aligned} \rm \dfrac{1}{C_{t}} &= 0.056 \times 100 + \dfrac{1}{2.02}\\\\&= 0.165 \;\rm M\end{aligned}[/tex]
Therefore, after 100 seconds the concentration is 0.165 M.
Learn more about the order of reaction here:
https://brainly.com/question/14810717
Identify the true statements regarding hydrogen bonding. Select all that apply. Group of answer choices Hydrogen bonding occurs when a hydrogen atom is covalently bonded to an N, O, or F atom.
Answer:
True
Explanation:
Hydrogen bonding occurs when hydrogen is covalently bonded to a highly electronegative element such as N, O, or F.
Hydrogen bonding affects several physical properties of molecules in which it occur. For example, the high boiling point of water is caused by intermolecular hydrogen bonding irrespective of the low relative molecular mass of water.
The statement stating the presence of hydrogen bonding between the hydrogen and N, O, and F has been true.
Hydrogen bonding has resulted when the electrostatic interaction has been found in the atoms that have been more electronegative than the Hydrogen atoms.
The electrostatic force helps in attracting the atoms towards the hydrogen and thereby the hydrogen bonding takes place. It has been a weak force present in the molecules. The hydrogen bonding can be easily breakable.
For more information about hydrogen bonding, refer to the link:
https://brainly.com/question/10904296
what is the bond energy required to break one mole of carbon-carbon bonds
Answer:
100 kcal of bond energy
What is the maximum number of electrons in the following energy level?
n = 4
Answer: 32 electrons
Explanation:
When hydrogen gas reacts with oxygen gas, water vapour is formed according to the
reaction 2H2 + O2 2H2O. If 3.00 mol of hydrogen gas react with 3.00 mol
of oxygen gas, which reactant will be the reactant in excess?
Explanation:
here's the answer to the question
Please help 15 points
What is the change in electrons for nitrogen in the
following reaction?
S + NO3 --> SO2 + NO
Nitrogen gained 4 electrons.
Because Nitrogen's redox number went from +6 to +2, it must have gained 4 electrons (-4) in order to achieve this number. Thus, Nitrogen is reduced.
