Answer:
electric balance, goggles, beaker
Explanation:
I did it and got it right
Which of the following is an oxide which is strongly acidic?
(a) Na2O.
(b) MgO
(c) SiO2.
(d) P2O5.
Answer:
answer of your question is 4th
Explanation:
P205
Describe how you would prepare a supersaturated solution
Answer:
A supersaturated solution contains more dissolved solute than required for preparing a saturated solution and can be prepared by heating a saturated solution, adding more solute, and then cooling it gently. Excess dissolved solute crystallizes by seeding supersaturated solution with a few crystals of the solute.
Explanation:
Which letter in the diagram represents the transition from liquid to gas?
A
B
C
D
Answer:
D
Explanation:
B is solid and liquid while D is liquid and gas
Answer:
Option ( D) is correct
The phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase.
Explanation:
A heating curve graphically represents the phase transitions that a substance undergoes as heat is added to it.
The liquid will begin to boil when enough heat has been absorbed by the solution that the temperature reaches the boiling point, where again, the temperature remains constant until all of the liquid has become gaseous water. At the atmospheric pressure of 1 atm, this phase transition occurs at 100o C (the normal boiling point of water). Liquid water becomes water vapor or steam when it enters the gaseous phase. Use the heat of vaporization ([latex]\Delta H_{vap}[/latex] ) to calculate how much heat was absorbed in this process: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex], where m is the mass of the sample of water.
After all of the liquid has been converted to gas, the temperature will continue to increase as heat as added. Again, the heat added that results in a certain change temperature is given by: [latex]q=m\cdot C_{H_2O(g)}\cdot \Delta T[/latex] . Note that the specific heat capacity of gaseous water is different than that of ice or liquid water.
phosphorus react with carbon
Answer:
Phosphorus atoms can bond with oxygen atoms to form ester groups. These can bond with carbon atoms, yielding a large number of organic phosphorus chemicals. These are found in many important biological processes
what is the atomicity of Sulphur?
Answer:
the atomicity of sulphur is 8
Explanation:
hope it helps
Which of the following elements would have the largest electronegativity value?
O cesium
Olithium
O carbon
O sodium
mendeleev's periodic table is studied even though it is considered to be defective
Answer:
This is because Mendeleev arranged the elements in order of increasing relative atomic mass.
Explanation:
Dmitri Mendeleev is one of the scientists that contributed to the development of periodic table in chemistry. He was able to organise elements into rows according to their atomic mass and into columns based on chemical and physical properties. This is the main reason why his periodic table is still studied even though it has some defects which include:
--> Grouping of elements that are not similar chemically: For example Copper and Silver bear no resemblance with the alkali metals, but they have been placed together in the first group.
--> Position of isotopes: According to his periodic table: Isotopes of an element must be given separate places in the periodic table because they have different atomic masses.
--> Electronic arrangement of elements: It failed to explain the electronic arrangement of elements.
--> Separation of chemically similar elements:
Elements that are chemically similar such as Gold and Platinum have been placed in separate groups.
In the following acid-base reaction,
Cl- is the
HCI(g) + H2O(l) →H30+(aq) + Cl(aq)
acid
base
conjugate
base
Answer:
conjugate base
Explanation:
The following equation is given in this question:
HCI(g) + H2O(l) → H30+(aq) + Cl-(aq)
In accordance to Brønsted–Lowry acid–base theory, an acid is a substance that loses an hydrogen ion (H+) or proton in an aqueous solution. This theory further indicated that the substance formed after an acid loses its hydrogen ion is called a CONJUGATE BASE.
In the above equation, HCl is the acid because it loses H+ while the substance formed after the loss of H+, which is Cl- is a conjugate base.
1. Necesitas un "cubo concentrado" (de esos que se usan para sazonar las comidas Maggie, ricostilla) dos vasos de vidrio o plástico y agua (caliente y fría). 2.Agrega al vaso con agua fria la mitad de un cubo concentrado y déjala reposar unos minutos. Prepara el segundo vaso con agua caliente y agrégale la otra mitad del cubo. 3. Argumenta tus observaciones en relación con lo observado y con la teoria vista. ¿Como influye la temperatura en este experimento?
Identifica las formas de energía mecánica
(cinética y potencial) que tienen lugar en diferentes puntos del movimiento en
un sistema mecánico (caída libre, montaña rusa, péndulo).
2 Tipos de Energía Mecánica
2.1 1. Energía hidráulica
2.2 2. Energía eólica
2.3 3. Energía Mareomotriz
3 Ejemplos de Energía Mecánica
3.1 1. Planta hidroeléctrica
3.2 2. Máquinas de Vapor
3.3 3. Motor de Combustión interna
3.4 4. Molinos de Viento
3.5 5. Un Juego de Billar
3.6 6. Motor eléctrico
3.7 7. Locomotora
3.8 8. Bala
3.9 9. Una pistola de Dardos
3.10 10. Pelota sobre una mesa
https://www.aura-energia.com/ejemplos-de-energia-mecanica/
Element 'X' forms a chloride with the formula XCl2, which is a solid with high melting point. X would most likely be in the same group of the periodic table as:
I) Si
2) Al
3) Mg
4) Na
pls pls answer fast
Answer:
Mg
Explanation:
Mg forms 2+ ions and mgcl2 has a melting point over 700°C I believe.
Can someone help me with this question ASAP
Is the graph more accurate with more atoms or less atoms?
Answer:
I would guess more atoms? but there is no graph attached
Which of the following are true for an element? (i)Atomic number= number of protons + number of electrons (ii)Mass number = number of protons+ number of neutrons (iii)Atomic mass= number of protons= number of neutrons (iv)Atomic number = number of protons = number of electrons
Answer:
ii and iv
Explanation:
atomic mass is the sum of protons and neutrons
protons ( postively charged) usually have the same number like electrons( negatively charged)
please help asap!!!!!!!!
The two waves in the diagram are occupying the same place at the same time. At what time will the interfering waves have an amplitude of zero? 1.0 3.0 4.0 7.0 Mark this and return
Answer: It’s 4.0
Explanation: I just took the test and got it right:)
Which of the following about a balanced chemical reactions is
NOT true?
O A properly written chemical equation will include the states of matter
for every substance in the reaction.
O The number of atoms of each element must be the same for both
reactants and products.
A balanced chemical equation must follow the Law of Conservation
of Matter
A balanced chemical equation must always include coefficients on
every reactant and product.
Answer:
A balanced chemical equation must always include coefficients on every reactant and product.
Explanation:
A balanced chemical equation does not need to include coefficients on every reactant and product.
For example, below is a balanced chemical equation in which the reactants and the products have no coefficients whatsoever:
NaOH(aq) + HCl (aq) -----> NaCl (s) + H2O (l)
Of course, a properly written chemical equation must include the states of matter of all the substances in the reaction and the number of atoms of each element must balance both in the reactant and product sides of the equation. Generally, a balanced chemical equation must obey the law of conservation of matter which opines that matter can neither be created nor destroyed but can only be converted from one form to another.
Hence, that a balanced chemical equation must always include coefficients on every reactant and product is not true.
Calculate the mass percent of carbon,oxygen, nitrogen and hydrogen in acetamide, C2H5NO.
Molar Mass:
O=16, N=14,C=12, H =1.
Answer:
40.68 % C
23.73 % N
8.47% H
27.12% O
Explanation:
The mass percent of an element X in a compound is calculated as the molar mass (MM) of X multiplied by the number of atoms of X in the compound, divided into the molecular weight (MW) of the compound, as follows:
mass percent of X = (MM(X) x number of atoms of X)/MW compound x 100
Thus, we first calculate the MW of acetamide (C₂H₅NO) by using the molar mass of the chemical elements C, H, N and O:
MW(C₂H₅NO) = (12 g/mol C x 2) + (1 g/mol H x 5) + 14 g/mol N + 16 g/mol O = 59 g/mol
Now, we can calculate the mass percent of each element (C, H, N, O) in C₂H₅NO:
Mass percent of C (2 atoms of C in 1 molecule of C₂H₅NO):% mass C = (12 g/mol x 2)/(59 g/mol) x 100 = 40.68 %
Mass percent of N (1 atom of N in 1 molecule of C₂H₅NO):% mass N = (14 g/mol x 1)/(59 g/mol) x 100 = 23.73 %
Mass percent of H (5 atoms of H in 1 molecule of C₂H₅NO):
% mass H = (1 g/mol x 5)/(59 g/mol) x 100 = 8.47 %
Mass percent of O (1 atom of O in 1 molecule of C₂H₅NO):
% mass O = (16 g/mol x 1)/(59 g/mol) x 100 = 27.12 %
The sum of the mass percents has to be equal to 100%:
40.68 % C + 23.73 % N + 8.47% H + 27.12% O = 100%
PLZ HELL ME WITH MY WORK
Answer:
Ba
Explanation:
If a quantity of this substance existed as a solid at a pressure of 0.75 atm and a temperature of 50°C, what phase
change(s) would occur if the temperature increased to 500°C?
a. Freezing and deposition
b. Melting and freezing
c. Condensation and sublimation
d. Melting and vaporization
write electronic configuration of chlorine in its ionic state?
Answer:
1s2 2s2 2p6 3s2 3p6
Explanation:
Chlorine is a groups 17 element. The halogens for ions by accepting one electron to form univalent negative ions.
Since chlorine normally contains seventeen electrons, the chloride ion consists of eighteen electrons.
Hence the electronic configuration of chlorine ion is; 1s2 2s2 2p6 3s2 3p6.
A 2.50 L container is filled with 175 g of argon; a. If the pressure is 10 atm, what is the temperature ? b if the temperature is 22K, what is the pressure ?
Answer:
A. 70 K
B. 3.16 atm
Explanation:
We'll begin by calculating the number of mole in 175 g of Ar. This can be obtained as follow:
Mass of Ar = 175 g
Molar mass of Ar = 40 g/mol
Mole of Ar =?
Mole = mass / molar mass
Mole of Ar = 175 / 40
Mole of Ar = 4.375 moles
A. Determination of the temperature.
Mole of Ar (n) = 4.375 moles
Volume (V) = 2.50 L
Pressure (P) = 10 atm
Gas constant (R) = 0.0821 atm.L/Kmol
Temperature (T) =?
PV = nRT
10 × 2.5 = 4.375 × 0.0821 × T
25 = 4.375 × 0.0821 × T
Divide both side by (4.375 × 0.0821)
T = 25 / (4.375 × 0.0821)
T ≈ 70 K
B. Determination of the pressure.
Mole of Ar (n) = 4.375 moles
Volume (V) = 2.50 L
Temperature (T) = 22 K
Gas constant (R) = 0.0821 atm.L/Kmol
Pressure (P) =?
PV = nRT
P × 2.5 = 4.375 × 0.0821 × 22
Divide both side by 2.5
P = (4.375 × 0.0821 × 22) / 2.5
P = 3.16 atm.
Explain the steps you would follow to make 500 mL of a 0.3 M solution of sucrose
(C12H22011) in the lab.
Answer:
see explanation
Explanation:
Solutions are prepared from one of three solute sources ...
- solid solute from manufacturer,
-liquid solute from manufacturer,
-stock concentrate of solute for dilution to lower concentrations.
In this problem, sucrose is a stock solid with a formula mass of 342.3 grams/mol. The amount of solid needed can be determined using the formula:
mass of solute needed (grams) = (Molarity needed x Volume needed in Liters x formula weight) / (decimal fraction purity of stock solid)
Molarity needed = 0.3M
Volume needed = 500 ml = 0.500 liters
Formula weight = 342.3 grams/mole
Purity factor (assumed) = 100% = 1.00 (should be posted on stock bottle label) For example, a 95% pure stock solid => purity factor of 0.95.
∴ grams of sucrose needed = (0.3M*)(0.500L)(342.3g/mole)/(1.00) =51.345 grams sucrose.
Measure 51.345 grams of sucrose into mixing vessel and add solvent water up to, but not to exceed 500 ml total volume. Mix until homogeneous.
Why boiling point is less at hilly station?
Help me please
The options are
A. Translation
B. Rotation
C. Enlargement
D.reduction
Answer:
C. Enlargement
Explanation:
Pls help!!!
You are given a type of element by a teacher and she asks you to identify it.What should you do?Explain your answer
Answer:
NAO SRESONDEPORR PQUEOU BUOBRRRA IGAD THCAAUSEI
Explanation:
Cual es la longitud de onda de un foton emitido durante la transicion desde el stado n=5 al estado n=3 en atomo Hidrogeno? Dar como respuesta de la longitud de onda en nm (nanometros)
Answer:
1302 nm
Explanation:
Del formulario de Rydberg para longitud de onda
1 / λ = R (1 / nf ^ 2 - 1 / ni ^ 2)
1 / λ = 1.097 × 10 ^ 7 (1/3 ^ 2 - 1/5 ^ 2)
1 / λ = 1.097 × 10 ^ 7 (0.11 - 0.04)
1 / λ = 1.097 × 10 ^ 7 (0.07)
= 1,302 × 10 ^ -6 m
o 1302 nm
Name the following compound NiBr2?
Answer:
the Name of NiBr2 is
Nickel(II) bromide
Nồng độ mol của 200ml dung dịch Nacl chứa 0,5 mol chất tan là :
Answer:
Explanation:
2,5M
Answer:
2,5m
Explanation:
c=n:v
plz answer (d) explain
Cu2+ is reduced to Cu.
Change in oxidation state is from +2 to 0
movement of water molecules without the use of energy
The answer is ‘Passive Transport’
movement of molecules without the use of energy is due to the shrinkage of water