Answer:
[tex] \huge 9[/tex]
Explanation:
The pH of a solution can be found by using the formula
[tex]pH = - log [ { H_3O}^{+}][/tex]
From the question we have
[tex]pH = - log(1 \times {10}^{ - 9} ) [/tex]
We have the final answer as
9Hope this helps you
Xenon tetrafluoride has two sets of lone pairs of electrons. What should be the relative positions of the two sets of lone pairs?Why?
Answer: Two equatorial positions so as to minimize the repulsion.
Explanation:
Formula used for calculating number of electrons :
[tex]\frac{1}{2}[V+N-C+A][/tex]
where,
V = number of valence electrons present in central atom = 8
N = number of monovalent atoms bonded to central atom = 4
C = charge of cation = 0
A = charge of anion = 0
Now we have to determine the hybridization of the [tex]XeF_4[/tex] molecule.
[tex]\frac{1}{2}[8+4-0+0]=6[/tex]
Bond pair electrons = 4
Lone pair electrons = 2
The number of electrons are 6 that means the hybridization will be [tex]sp^3d^2[/tex] and the electronic geometry of the molecule will be octahedral.
The molecular geometry will be square planar as two alternate positio ns will be occupied by lone pair of electrons so as to minimize the repulsion.
What indicator of a chemical reaction could be measured using a thermometer?
Answer:
heat production
Explanation:
calculate the pH of 5.9x10^-4
Answer:
The answer is 59
Explanation:
what is the combined gas law equation
Answer:
\frac {P_{1}V_{1}}{T_{1}}=\frac {P_{2}V_{2}}{T_{2}}
Explanation:
Gay-Lussac's law states that at constant volume, the pressure of a gas is directly proportional to the absolute temperature, P ∝ T at constant V. These three gas laws can be combined into a so-called combined gas law, P 1 V 1 T 1 = P 2 V 2 T 2.
Helium decays to form lithium. Which equation correctly describes this decay? Superscript 6 Subscript 2 Baseline Upper H e right arrow Superscript 3 Subscript 3 Baseline Upper L i + Superscript 0 Subscript negative 1 Baseline e Superscript 6 Subscript 2 Baseline Upper H e right arrow Superscript 6 Subscript 3 Baseline Upper H + Superscript 0 Subscript negative 1 Baseline e Superscript 6 Subscript 2 Baseline Upper H e right arrow Superscript 6 Subscript 3 Baseline Upper L i + Superscript 0 Subscript negative 1 Baseline e Superscript 6 Subscript 2 Baseline Upper H e right arrow Superscript 6 Subscript 3 Baseline Upper L i + Superscript 0 Subscript 1 Baseline e
Answer:
Superscript 6 Subscript 2 Baseline Upper H e right arrow Superscript 6 Subscript 3 Baseline Upper L i + Superscript 0 Subscript negative 1 Baseline e
Explanation:
Helium decays by beta emission, in beta emission, the mass number of the parent and daughter nuclei are the same but the atomic number of the daughter nucleus increases by one hence it is found one place to the right of its parent in the periodic table.
Having said this, the decay of Helium to lithium may be written as follows;
6/2He -> 6/3Li + 0/-1e
Answer:
C
Explanation:
Edge 2020
An atom does not have to have equal numbers of protons and _________________ in the nucleus.
Answer:
the answer is neurtons
Explanation:
which elements are solid at room temperature
Answer:bromine , neon , helium , argon , lithium , beryllium
Explanation:
Elements can be divided into three state that are solid, liquid and gas depending the intermolecular forces of attraction, distance between the particles etc. Lithium, beryllium, boron, carbon, sodium, magnesium, iron, copper, etc. are solid at room temperature.
What is element?Element generally consist of atoms or we can atoms combine to form element. Atoms of an element is always same, means all the properties of all atoms of one type of element is same.
Two or more than two atoms with different physical or chemical properties can not combine together to form an element. Elements can be solid liquid or gas at room temperature.
Therefore, Lithium, beryllium, boron, carbon, sodium, magnesium, iron, copper, etc. are solid at room temperature.
To know more about element, here:
https://brainly.com/question/8460633
#SPJ2
Which produces the most energy? A. passing 5 kg of water through a hydroelectric power plant. B. fissioning 5 kg of uranium. C. burning 5 kg of gasoline. or D. fusing 5 kg of hydrogen.
Answer:
D. fusing 5 kg of hydrogen.
Explanation:
The adult dosage of diphenhydramine, an antihistamine, is 50.0 mg. A 24 lb child should only receive 20.0% of the adult dose. Calculate this dose in milligrams.
The amount that the child should receive is 10 mg.
What is a dose?The term dose refers to the amount of drugs that a person should take. The dose of the drug is in proportion to the magnitude of the illness. The more severe the symptoms, the higher the dosage.
Since the child is to receive only 20% of the adult dose, we have;
20/100 * 50.0 mg
= 10 mg
The amount that the child should receive is 10 mg.
Learn more about dose:https://brainly.com/question/12971282
#SPJ1
An unknown gas with a formula of HX is contained in a 25.0 L tank at 1.2 atm and 25.0 oC. What is the chemical formula of the gas if the mass of the gas is 44.7 g?
Answer:
HCl
Explanation:
Volume = 25L
Temperature = 25.0 oC + 273 = 298 K (Converting to kelvin units)
Pressure = 1.2 atm
Mass of gas = 44.7g
Formular of gas = HX
To solve this, we have to know the identity of X. One qay to do that is by obtaining the molecular mass of the compound.
To get the molar mass, we need the number of mole.
Using the ideal gas equation;
PV = nRT
where R = gas constant = 0.082 057 L atm K−1 mol−1
n = PV / RT
n = 1.2 * 25 / 0.082 057 * 298
n = 30 / 24.45
n = 1.227 mol
The relationship between number of moles and molar mass is given as;
Nummber f moles = mass / molar mass
Molar mass = mass / Number of moles
Molar mass = 44.7 / 1.227
Molar mass = 36.43 g/mol
Molar mass of gas X = Molar mass of H + Molar mass of X
36.43 = 1 + X
X = 36.43 - 1 = 35.43
Chlorine is the only element with molar mass approximate to 35.43
Hence X = Cl
The chemical formular = HCl
How does having knowledge about viscosity may affect you in simple ways in your daily life?
Viscosity is an crucial factor in food preparation and serving. Cooking oils' viscosity may or may not change as they heat, but many become much more viscous as they cool.
What is viscosity?Viscosity refers to the resistance of a fluid (liquid or gaseous state) to a shape shift or mobility of neighboring portions relative to one another. Viscosity indicates flow resistance.
Gathering viscosity data on a material allows manufacturers to predict how the material will start behaving in the real world. For example, if toothpaste does not have the correct viscosity, it may be difficult or impossible to pump out of the tube.
Thus, it is important to have the knowledge of viscosity.
For more details regarding viscosity, visit:
https://brainly.com/question/13385698
#SPJ1
How is wavelength measured (Select all that apply. from the trough (bottom) of one wave to the trough of the next wave
from the trough (bottom) of one wave to the crest (top) of the next wave
from the crest (top) of one wave to the crest (top) of the next wave
from the crest (top) of one wave to the trough (bottom) of the next wave
Answer:
The first two
Wavelength is measured from crest to crest. Amplitude is from trough to crest or crest to trough
How many grams are in 0.040 moles zirconium (Zr)? Only 2 significant numbers?
Mass of Zirconium (Zr) in 0.040 moles : 3.6 g
Further explanationThe mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
Moles can also be determined from the amount of substance mass and its molar mass
[tex]\tt n(mol)=\dfrac{m(mass)}{MW(molecular~weight)}[/tex]
moles of Zirconium : 0.04
mass of Zirconium (MW=91,224 g/mol) :
[tex]\tt mass=mol\times MW\\\\mass=0.04\times 91,224\\\\mass=3.6~g[/tex]
GIVEING BRAINLIST
ATP is a(1 point)
storable form of energy.
usable form of energy.
form of energy that can be used and stored.
form of energy that can be stored and released as heat.
Answer:
ATP is a stored form of energy
Explanation:
it is the main source of this
How can carbon dating be used to study the history of the earth?
Type the following formulas in the boxes in order of increasing boiling point: RbF, CO2, CH3OH, CH3Br.
Answer:
CO2 < CH3Br < CH3OH < RbF
Explanation:
The boiling point of the compounds can be determined in terms of the strength of the intermolecular forces present in each compound.
Intermolecular forces are weak forces joining non-polar and polar molecules together. We have London dispersion forces, dipole-dipole forces of attraction, and hydrogen bonding.
London dispersion forces are weak attractions found between non-polar and polar symmetrical molecules. They are the weakest of all the electrical forces and they act between atoms and molecules e.g CO2
The dipole-dipole attractions are forces of attraction existing between polar unsymmetrical molecules. The dipole-dipole force of attractions is much stronger than London dispersion forces but weaker than Hydrogen bonding. e.g CH3Br
Hydrogen bonding is a special dipole-dipole attraction between polar molecules in which a hydrogen atom is directly joined to a highly electronegative atom (e.g. oxygen, nitrogen, or fluorine). Here, the bond in CH3OH is a hydrogen bond.
Ionic bonding is a bond that is formed between two kinds of atoms having a large electronegative difference such as in RbF,
Thus, in increasing order of boiling point;
CO2 < CH3Br < CH3OH < RbF
What nuclide undergoes fission to form molybdenum-103, atomic number 42, tin-131, atomic number 50, and two neutrons?
Element symbol: _______ mass number: _______
Answer:
The correct answer is Pu, 234.
Explanation:
In the given case, let us consider the reactant as X. Now the mass number (balanced) on both the sides will be,
Mass of X = Mass of Molybdenum + Mass of Tin + Mass of neutrons
M = 1 * 103 + 1 * 131 + 2 * 0
M = 234
Now the atomic number (balanced) on both the sides,
Atomic number of X = Atomic number of Molybdenum + Atomic number of Tin + Atomic number of neutrons
A = 1*42 + 1*50 + 2*1
A = 94
The atomic number 94 is for the element Plutonium, whose symbol is Pu. Thus, the reactant is 234-Pu.
True or false: oceans have no efect on the temperature on Earth’s land.
Will give out free Brainiest, I know there are thirsty people out there :D
Answer:
False
Explanation:
Answer
is it FALSE?
I always answer question but people don't ever give me brainiest that why i got 0
What is the maximum number of electrons that can be present in each principal energy level of hydrogen?
Answer:
Each principal energy level has one sublevel containing one orbital, an s orbital, that can contain a maximum of two electrons.
Explanation:
Answer:
2n
Explanation:
How many valence electrons are in Sn+2? please answer asap thank you
Answer:
2 electrons
Explanation:
HC1O4 + P4010 ->
H3PO4 + Cl₂O7
How do I balance it?
Answer: watch Video of HC1O4 + P4010 -> H3PO4 + Cl₂o7 How Do I Balance It?
bing.com/videos
Explanation: video is called How to Balance HClO4 P4O10 = H3PO4 Cl2O7 (Perchloric acid Phosphorus pentoxide)
Play How to Balance HClO4 P4O10 = H3PO4 Cl2O7 (Perchloric acid Phosphorus pentoxide)
2:22 minute video
How to Balance HClO4 P4O10 = H3PO4 Cl2O7 (Perchloric acid Phosphorus pentoxide)
what is percentage composition?
Answer:
The percent composition of a component in a compound is the percent of the total mass of the compound that is due to that component. To calculate the percent composition of a component in a compound: Find the molar mass of the compound by adding up the masses of each atom.
A physical change is when the form or shape of a substance changes, but
the chemical structure remains the same. *
True
False
The combustion of propane C,H, produces carbon dioxide and steam.
CH,(8) + 50,(8) — 3C0,(8) + 4H2O(1)
How many moles of CO2 are produced when 7.5 mol of propane are burned in an excess of oxygen?
A. 15 mol
B. 23 mol
C. 3.8 mol
D. 2.5 mol
Answer:
23 moles
Explanation:
Given data:
number of moles of propane = 7.5 mol
Number of moles of carbon dioxide produced = ?
Solution:
Chemical equation:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Now we will compare the moles of propane and carbon dioxide.
C₃H₈ : CO₂
1 : 3
7.5 : 3/1×7.5 = 22.5
22.5≅ 23 moles
Selenic acid (H2SeO4) forms when solid selenium dioxide reacts with gaseous oxygen and liquid water to form aqueous selenic acid.
Part A
Enter a balanced chemical equation for this reaction.
Express your answer as a chemical equation. Identify all of the phases in your answer.
Answer: 2SeO2(s)+O2(g)+2H2O(l)→2H2SeO4(aq)
Explanation:
Start with the unbalanced equation by writing chemical formulas for each of the reactants and products:
SeO2(s)+O2(g)+H2O(l)→H2SeO4(aq)
Count the number of each atom on each side of the equation to determine whether the equation is balanced:
Reactants: 1 Se atom, 5 O atoms, 2 H atoms
Products: 1 Se atom, 4 O atoms, 2 H atoms
Balance the number of oxygen atoms by adding a coefficient of 2 to aqueous selenic acid on the products' side of the reaction. Then, balance the hydrogen atoms by adding a coefficient of 2 to liquid water on the reactants' side of the reaction. Finally, balance the selenium atoms by adding a coefficient of 2 to solid selenium dioxide on the reactants' side of the reaction to give the following balanced equation:
2SeO2(s)+O2(g)+2H2O(l)→2H2SeO4(aq)
The balanced chemical equation for this reaction is
[tex]\rm2SeO_2(s) + O_2(g) + 2H_2O(l) \rightarrow 2H_2SeO_4 (aq)[/tex]
What are balanced chemical equation?A balanced chemical equation is defined as a chemical reaction in which the number of atoms of each elements in the reaction and the total charge is same for both the reactants and the products.
It involves the addition of stoichiometric coefficients of the reactants and products.
Selenic acid is majorly used in protecting and changing the color of steel, especially the steel parts on firearms.
Thus, the balanced chemical equation for this reaction is
[tex]\rm2SeO_2(s) + O_2(g) + 2H_2O(l) \rightarrow 2H_2SeO_4 (aq)[/tex]
To learn more about balanced chemical equation, refer to the link below:
https://brainly.com/question/28294176
#SPJ2
Which type of precipitation occurs when the water vapor in a cloud freezes to form ice crystals?
Answer:snow i think
Explanation:
Answer:
snow
Explanation:
A 1.00 g sample ofNH4N03 is decomposed in a bomb calorimeter. The temperature increases by 6.12 oc. What is the molar heat of decomposition of NH4N0.1
This question is incomplete, the complete question is;
A 1.00 g sample of NH4NO3 is decomposedin a bomb calorimeter. The temperature increases by 6.12°C. What is the molar heat of decomposition for ammonium nitrate?
Molar mass, NH4NO3 80.0 g/mol
Calorimeter Constant 1.23 kJ/°C
Answer:
the molar heat of decomposition for ammonium nitrate is - 602.4 kJ/mol
Explanation:
Given that;
change in temperature ΔT = 6.12 °C
Calorimeter Constant C = 1.23 kJ/°C
Molar mass, NH4NO3 = 80.0 g/mol
we know that;
Heat gained by the calorimeter (Q1) = Heat lost by the decomposition of NH4NO3 (Q2)
Q1 = C × ΔT
Q1 = (1.23 kJ/K) × (6.12 K) = 7.53 kJ
Q value we get becomes negative since we are talking about reaction and not calorimeter
hence
Q1 = - 7.53 kJ
now
1 g NH4NO3 decomposed, - 7.53 kJ of heat is released
so if 80 g which is 1 mol NH4NO3 decompose, the heat will be;
(80 g/mol x -7.53 kJ) / 1 g = - 602.4 kJ/mol
Therefore the molar heat of decomposition for ammonium nitrate is - 602.4 kJ/mol
What is the mass (in grams) of 255ml of mercury if mercury has a density of 13.34 grams per ml? (Remember significant digits in answer)
The mass in grams of 255mL of mercury if it has a density of 13.34g/mL is 3401.7g.
How to calculate mass?The mass of a substance can be calculated by multiplying the volume of the substance by its density as follows:
Mass = density × volume
According to this question, 255mL of mercury has a density of 13.34g/mL. The mass is calculated as follows:
Mass = 13.34g/mL × 255mL
Mass = 3401.7g
Therefore, the mass in grams of 255mL of mercury if it has a density of 13.34g/mL is 3401.7g.
Learn more about mass at: https://brainly.com/question/6107689
#SPJ1
Nuclear decay occurs according to first-order kinetics. How long will it take for a sample of radon-218 to decay from 99 g to 0.50 g? The half-life of radon-218 is 35 milliseconds.
a. 2.6 x 102 ms.
b. 2.0 10 ms.
c. 1.1 x 10 ms.
d. 6.6 x 102 ms.
Answer:
a. 2.6 x 102 ms
Explanation:
Initial mass [Ao] = 99 g
Final mass [A] = 0.50 g
Half life (t1/2) = 35 ms
Time ( t ) = ?
]The integrated rate law for first order reactions is given as;
To obtain k, we look at the expression for the half life of a first order reaction;
t1/2 = 0.693 / k
k = 0.693 / 35 = 0.0198 ms-1
ln[A] = ln[Ao] - kt
kt = ln[Ao] - ln[A]
t = ( ln[Ao] - ln[A] ) / k
t = ( ln(99) - ln (0.50) ) / 0.0198
t = 5.288 / 0.0198
t = 267.07 ms
correct option is;
a. 2.6 x 102 ms
write net ionic equations for the reaction, if any, that occurs when aqueous solutions of the following are mixed. a. ammonium sulfate and barium nitrate
Answer:
SO₄²⁻(aq) + Ba²⁺(aq) ⇒ BaSO₄(s)
Explanation:
Let's consider the molecular equation that occurs when aqueous solutions of ammonium sulfate and barium nitrate are mixed.
(NH₄)₂SO₄(aq) + Ba(NO₃)₂(aq) ⇒ BaSO₄(s) + 2 NH₄NO₃(aq)
The complete ionic equation includes all the ions and insoluble species.
2 NH₄⁺(aq) + SO₄²⁻(aq) + Ba²⁺(aq) + 2 NO₃⁻(aq) ⇒ BaSO₄(s) + 2 NH₄⁺(aq) + 2 NO₃⁻(aq)
The net ionic equation includes only the ions that participate in the reaction and the insoluble species.
SO₄²⁻(aq) + Ba²⁺(aq) ⇒ BaSO₄(s)