Answer:
19 protons, 20 neutrons and 18 electrons.
Explanation:
The atomic number gives the number of protons 19
p = 19
The atomic mass is the sum of the protons and neutrons
p + n = 39 p = 19
put p into the equation and solve for n the neutrons.
19 + n = 39
Subtract 19 from both sides
19 − 19 + n = 39 − 19
n = 20
The number of electrons equals the number of protons in a neutral atom. The positive charge equals the negative charge. The negative charge is the number of electrons. This ion has a charge of +1. So solve for the negative charge.
− 19 + 1 = − 18
The negative charge is -18 so
e = 18
Anhydrous aluminium chloride contain 20.2% by mass of aluminium show that the emprical formula for anhydrous aluminium chloride
Answer:(d) has a high melting point because it has a giant covalent structure ... (i) Calculate the maximum mass of propyl ethanoate that can be made from 7.20 g of ethanoic ... (c) Anhydrous aluminium chloride contains 20.2% by mass of aluminium. (i) Show that the empirical formula for anhydrous aluminium chloride is A
Explanation:
Please help please help
Answer:
sry I don't know much about chemistry
what is the balanced equation of magnesium carbonate decomposes on heating to form magnesium oxide and carbon dioxide
Answer:
ExplaAt high temperatures MgCO3 decomposes to magnesium oxide and carbon dioxide. This process is important in the production of magnesium oxide. This process is called calcining: MgCO3 → MgO + CO2 (ΔH = +118 kJ/mol)
nation:
Please answer the question
Answer:
Oxygen is the nearest noble gas
PLEASE HELP ASAP Put these events in order, from earliest to latest.
-the first fusion bomb is tested
-uranium atoms are split
-atomic bombs are dropped on Japan at the end of world war ll
-the first nuclear-powered submarine is put into action
-Enrico fermi creates the first known nuclear chain reaction
Answer:
1) Uranium atoms are split
2) Enrico Fermi creates the first known nuclear chain reaction
3) Atomic bombs are dropped on Japan at the end of WWll
4) The first fusion bomb is tested
5) The first nuclear-powered submarine is put into action
can someone pls tell me if this is correct? and also if possible, pls explain the difference between fractional and simple distillation, thank you sm <3
Explanation:
everything can be found in the picture
The Sulphate of x is XSO4 valency of x is
Answer: m mm
/lk ac
Explanation:
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Please help me with this in the picture I need 8 thing wrong and 8 what should they do right
What is the volume of the fluid in the graduated cylinder measured to the correct degree of precision?
Use this media to help you complete the question.
43.4 mL
44.0 mL
43.42 mL
44.10 mL
Answer:
44.10
Explanation:
got it right on odessyware
12. Organelles allow eukaryotic cells to carry out more functions than prokaryotic cells.
True or false?
Answer:
True po
Explaination :
I hope it helps
"Para enfriar algo rápidamente se hace una mezcla de hielo con sal o, si tiene precaución, alcohol. El punto de congelación bajará y el hielo se derretirá rápidamente. Pese a aparentar haberse perdido el frío, la mezcla formada estará en realidad a unos cuantos grados bajo cero y será mucho más efectiva para enfriar que los cubos de hielo sólidos". El fenómeno relatado corresponde a una consecuencia de:
La pregunta está incompleta, la pregunta completa es;
"Para enfriar algo rápidamente, haga una mezcla de hielo cd sal o, si
tenga cuidado, alcohol. El punto de congelación bajará y el hielo
derretir rápidamente. A pesar de parecer haber perdido el frío, la mezcla
formado será en realidad unos pocos grados bajo cero y será
mucho más eficaz para enfriar que los cubitos de hielo sólido. "La
fenómeno reportado corresponde a una consecuencia de: *
una. Aumento del punto de ebullición
B. disminución de la presión de vapor
C. aumento de la presión de vapor
D. disminución del punto de congelación
Answer:
D
Explanation:
Esta pregunta recuerda las propiedades coligativas. Las propiedades coligativas son propiedades de sustancias que dependen de la cantidad de sustancia presente.
El punto de congelación es una propiedad coligativa. Se sabe que la presencia de impurezas reduce el punto de fusión y congelación. Esto se llama depresión del punto de congelación.
Por lo tanto, la observación registrada en la pregunta es el resultado de la disminución del punto de congelación.
is it true that the most reactive metals are quite plentiful in the Earth's crust?
Answer:
yes
Explanation:
as it had got crushed down in the dinosaurs age
who's know this one?
sand + witch?
Answer:
The Magician who lives in sand is called sand witch.
And sandwich is The name of one kind of food.
Answer:
Sandwich its food you eat it
Explanation:
A student who is performing an experiment must measure out 0.02-mL of 0.50-M HCl. The most accurate piece of equipment to measure the quantity would be a?
A) 50 mL buret
B) 25 mL graduated cylinder
C) 10 mL cylinder
D) 1 mL pipet
Answer:
Choice D) 1 mL pipet
Explanation:
If you are trying to extract 0.02 mL of HCl, you are going to need a piece of equipment that can measure very small units. Thus, Choice D would be the correct answer.
ffg full form
gti
ccc
Answer:
Grand Tourer Injection
4 Calculate the mass of tin that can be extracted from 100 kg of tin ore that contains
1% tin by mass. Calculate the mass of waste produced.
Answer:
formula for calculating mass is
first U will HV to find number of moles
m=n×M
Someone help me with this science question pls
Answer: Can i see the question
Explanation:
Which of the following would be expected to have the lowest boiling point?
CH3CH2CH2CH3, CH3CH2NHCH3, NH2CH2CH2NH2, CH3CH2CH2NH2
O CH3CH2NHCH3
O NH2CH2CH2NH2
O CH3CH2CH2NH2
O CH3CH2CH2CH3
Answer:
CH3CH2CH2CH3
Explanation:
The boiling point of a compound depends on the nature of intermolecular interaction between the molecules of the compound.
If a molecule is nonpolar and has a low molecular mass, then its molecules are most likely held together only by weak intermolecular bonds such as dispersion forces. These forces are easily broken and the molecules move apart hence the molecule possess a low boiling point.
Polar molecules and molecules having higher molecular mass tend to have higher boiling points.
Among all the compounds listed, CH3CH2CH2CH3 is non polar and has the lowest molecular mass hence it exhibits the least boiling point.
7. A sample of a compound that contains only chlorine and oxygen reacts with excess hydrogen to produce 0.233 grams of hydrochloric acid and 0.403 grams of water. Determine the empirical formula of this compound.
Answer:
ClxOy + H2 > HCl + H2O
HCl = 0.233/37 = 0.006 mol H2O = 0.403/180.02 mol
HCl = 0.006/0.022 H2O = 0.022/0.006
= 1 = 4
Cl2O4 + 5H2 > 2HCl + 4H2O
I'm think that's the answer
rare earth elements plz
Answer:
Rare earth elements are lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium - that appear in low concentrations in the ground.
Explanation:
The rare earth elements (REE) are a set of seventeen metallic elements. These include the fifteen lanthanides on the periodic table plus scandium and yttrium. Rare earth elements are an essential part of many high-tech devices.
In the chemical reaction between aqueous magnesium chloride and sodium metal, what chemical amount (mol) of magnesium metal can be precipitated (produced) with 12.6 mol of sodium metal?
Answer:
6.3moles
Explanation:
The balanced equation of the reaction described above between aqueous magnesium chloride and sodium metal is as follows:
MgCl2(aq) + 2Na(s) → 2NaCl(aq) + Mg(s)
From the above equation, 2 moles of sodium metal (Na) produces 1 mole of Magnesium metal (Mg)
Hence, 12.6 mol of Na will produce (12.6/2) mol of Mg.
12.6/2 = 6.3moles of Mg metal.
Which would have more mass: a mole of sodium or a mole of copper? How do you know?
Answer:
copper
Explanation:
so for this you can work out the mass for both and compare
so mass = moles × mr
so mass of sodium = 1 × 23= 23 g
and mass of copper = 1 × 63.5= 63.5 g
so copper have more mass :)
SOMEONE HELP chemistry
AMSWER IN THE ATTACHMENT.
Increasing the concentration increases the speed of reaction by... increasing the number of collisions between products increasing the amount of energy in the system increasing the number of collisions between reactants lowering the activation energy of the reaction
Answer: increasing the number of collisions between reactants
Explanation:
A reaction is possible due to collisions between the reactants to create products. If we increase the concentration of reactants then that means that we are increasing the molecules of the reactants which would give them more chances to collide and make products.
For instance, using a non-chemistry example, if there are few cars in a large city, the accidents there will be less because the cars will have such space that they wouldn't collide with each other. If the number of cars in the city is increased however, there is now less space and more chances for cars to collide.
Question 24 Multiple Choice Worth 2 points)
[BWS.02] Why is science important for society?
Answer:
Because the scientific knowledge itself helps solve many basic human needs and it also improves how humans live and their standards. For example, without science medications wouldn´t exist and many technological devices we use now-a-days. We´re surrounded by science, we just don´t really notice it.
The reactants of two chemical equations are listed.
Equation 1: CuSO4 and NaOH
Equation 2: Fe and CuSO4
Based on the type of reaction, which reaction can be used to extract copper metal from copper sulfate solution?
A - Equation 2, because Fe being more reactive, replaces Cu from CuSO4
B - Equation 2, because Fe being more reactive, replaces S from CuSO4
C - Equation 1, because Na being more reactive, exchanges position with Cu in CuSO4
D - Equation 1, because Na being more reactive, exchanges position with S in CuSO4
The reaction that can be used to extract copper metal from copper sulfate solution would be equation 2.
Fe will displace Cu from CuSO4 because it is more reactive. In other words, Fe ranks higher than Cu in the reactivity series.
Thus: [tex]Fe + CuSO_4 ---> Cu + FeSO_4[/tex]
Even though Na will displace Cu from CuSO4, equation 1 will result in the formation of Cu(OH)2 instead of free Cu because it is a double replacement reaction.
More on copper production can be found here: https://brainly.com/question/13677872?referrer=searchResults
The blood must keep moving round the body to keep the rate of diffusion high explains why
Answer:
red blood cells and diffusion.
Explanation:
this process involves red blood cells and diffusion. Red Blood cells (RBCs) are a type of blood cell whose role is to transport oxygen from the lungs to the peripheral tissues of the body. Oxygen diffuses from the alveoli of the lungs in to the RBC's, where it binds to hemoglobin.
Diffusion is a very important process within the human body and is essential to the transport of molecules within a number of organs including the lungs, kidneys, stomach and eyes. The lungs process millions of tiny air sacs that are called alveoli, each of which are in close contact with capillaries.
When an Li atom becomes an Li+ ion, the Li atom
Answer:When a lithium atom forms an Li+ ion, the lithium atom (1) gains a proton (2) gains an electron (3) loses a proton (4) loses an electron
Which diagram shows how the covalent bonds most likely form in a phosphorous trichloride molecule?
The first diagram shows the covalent bonds most likely form in a phosphorous trichloride molecule. Hence, option A is correct.
What is a covalent bond?Covalent bonds can be polar or nonpolar depending on the electronegativity difference between the atoms involved. In a nonpolar covalent bond, the electrons are shared equally between the atoms. In a polar covalent bond, the electrons are shared unequally.
Phosphorus trichloride (PCl₃) is a covalent compound that consists of one phosphorus atom and three chlorine atoms. The three chlorine atoms are located in a plane that is perpendicular to the phosphorus atom, forming an equilateral triangle with bond angles of 120°.
The molecule has a trigonal pyramidal shape, with the phosphorus atom at the apex and the three chlorine atoms at the base of the pyramid. The fourth hybridized orbital of phosphorus contains a lone pair of electrons that is located above the trigonal plane, giving the molecule a distorted tetrahedral geometry.
Thus, option A is correct.
To learn more about the covalent bond, follow the link:
https://brainly.com/question/10777799
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