Answer:
The filter flask and the vacuum trap consist of heavy-walled glassware. You should use thick-walled tubings as well. Normal tubing that you use as water hoses will collapse under vacuum.
For vacuum filtration, thick walled tubings are best as they can withstand the pressure which is applied during filtration.
What is vacuum filtration?It is a filtration technique which works faster .This is because water is suck out the air in the vacuum flask and Buchner funnel by flowing it through the aspirator.
Filter at the bottom separates the solids from the liquids.Solid residue at top of funnel can be easily dried. The filtration takes place effeciently in presence of vacuum .
There is a rubber conical seal which ensures that the apparatus is hermetically closed,maintains vacuum in apparatus and avoids physical points of stresses.
Vacuum filtration is faster than gravity filtration and is more efficient leading to purer liquid. It is of much importance in crystallization.
Learn more about vacuum filtration,here:
https://brainly.com/question/28503164
#SPJ2
Fill in the blank
Atomic Number (____) = the number of ________________ or the number of ___________________.
Atomic Mass Number (____) = the number of ________________ PLUS the number of ______________.
Answer:
Atomic number (smaller number) =number of protons or number of electrons
mass number ( larger number) =number of protons plus the number of neutrons
What is the name of this process?
Answer:
Fertilization
Explanation:
Fertilization occurs when the nucleus of both a sperm and an egg fuse to form a diploid cell, known as zygote. The successful fusion of gametes forms a new organism.
Why does the reactivity of metals increase from right to left on the periodic table?
Metals on the right have fewer protons, making it harder to attract electrons from other atoms.
Metals on the right have more protons, causing valence electrons to be held more strongly.
Metals on the right have more valence energy levels, so the ability of the nucleus to attract electrons is reduced.
Metals on the right have fewer valence energy levels, so electrons are closer to the nucleus and harder to pull away.
Why does the reactivity of metals increase from right to left on the periodic table?
Metals on the right have fewer protons, making it harder to attract electrons from other atoms.
Metals on the right have more protons, causing valence electrons to be held more strongly.
Metals on the right have more valence energy levels, so the ability of the nucleus to attract electrons is reduced.
Metals on the right have fewer valence energy levels, so electrons are closer to the nucleus and harder to pull away.
Which feature is unique to Group 18 nonmetals?
They have more exceptions to reactivity rules.
They are very nonreactive.
They are very reactive.
They follow a different pattern of reactivity.
Which of the following combination of elements is the most reactive?
Na and Br
Cs and Br
Cs and I
K and I
How does Rb bond with other elements?
Rb loses two electrons.
Rb gains two electrons.
Rb loses an electron.
Rb gains an electron.
The characteristics of the reactivity of the periodic table allows to find the correct answers to the different questions are:
1) Metals on the right have more protons, causing valence electrons to be held more strongly.
2) They are very nonreactive.
3) Na and Br
4) Rb loses an electron
1) The reactivity of a chemical element is the tendency to combine with others, this increases as it has fewer electrons in its last layer and since they are more weakly bonded.
Consequently, halogens have seven electrons in their last shell tends to attract an electron to remain with the full level and the alkaline that an electron has in the last shell tends to lose the electron to remain with a complete shell.
If we examine the periodic table the number of electrons in the last shell decreases from right to left.
Let's review the different claims:
a) False. The elements on the right side have a higher atomic number, therefore more protons.
b) True. The elements have more protons therefore it has to attract other electrons and the reactivity decreases.
c) False. As it has more electrons, it has more energy levels, losing all the electrooens is more difficult, so the reactivity decreases.
d) False. By having more electrons it has more energy levels.
2) What is the unique characteristic of the elements of group 18
The elements of group 18 are the noble gases, they have their last full layer therefore they do not have.
the correct answer is: They are very nonreactive.
3) The reactivity in the period table decreases with increasing period therefore the element of period 3 is the most reactive in this case Sodium and Halogen of group 5 is the most reactive in this case Bromine.
the compound Na and Br is the most reactive of all.
4) Rubidium has 1 electron in its last shell, both in a chemical reaction pole loses the electron.
the correct answer is: Rb loses an electron
In conclusion, using the characteristics of the reactivity of the periodic table, we can answer the different questions..
1) Metals on the right have more protons, causing valence electrons to be held more strongly.
2) They are very nonreactive.
3) Na and Br
4) Rb loses an electron
Learn more here: brainly.com/question/20970885
The whole Patterns of Reactivity Quick Check for Honors Chemistry is
1) B. Metals on the right have more protons, causing valence electrons to be held more strongly.
2) B. by gaining electrons
3) B. They are very nonreactive
4) A. Cs and Br
5) A. Rb loses an electron
In a chemical reaction, the arrangement of atoms blank a reaction are rearranged blank the reaction.
Answer:
i dont care to you
Explanation:
cause you are tuyo
Which of the following can form a hydrogen bond with the HF molecule?
Answer:
helium
(He)
Explanation:
helium
(He)
List a few properties that elements in Group 1 have in common.
Answer:
The alkali metals are a group of chemical elements in the periodic table with the following physical and chemical properties:
shiny.
soft.
silvery.
highly reactive at standard temperature and pressure.
readily lose their outermost electron to form cations with a charge of +1.
Explanation:
have a great day
If a substance has a mass of 0.00235 grams and you need the mass in milligrams, will the number appear to become smaller or larger
Someone pls help me I will make you brain
Answer:
nosé
Explanation:
wadsdfc evdcaedc<dc
Answer:
second one
Explanation:
hello can anyone pls help question in picture thx
Explanation:
Chlorine is a non metal so covalent bond. KBr has K metal and Br non metal of opp. charges so ionic bond. Na is a metal so ionic bond. NaCl has Na as metal and Cl as a non metal so ionic bond.
D is incorrect
what is the relationship between temperature and pressure pls
Answer:
When the temperature of a system goes up, the pressure also goes up, and vice versa. The relationship between pressure and temperature of a gas is stated by the Gay-Lussac's law.
Answer:
We find that temperature and pressure are linearly related, and if the temperature is on the kelvin scale, then P and T are directly proportional (again, when volume and moles of gas are held constant); if the temperature on the kelvin scale increases by a certain factor, the gas pressure increases by the same factor.
Which substance tends to form anions when bonding with other elements?
oxygen
calcium
argon
sodium
Answer:
A) Oxygen
Explanation:
i just took the test.
A sample of 8.00 g of Mg(OH)2 is added to 24.2 mL of 0.205 M HNO3. How many moles of Mg(OH)2 our present after the reaction is complete?
The amount of Mg(OH)2 present after the reaction is complete is 0.136 moles of Mg(OH)2.
The equation of the reaction is;
2HNO3(aq) + Mg(OH)2(aq) -------> Mg(NO3)2(aq) + 2H2O(l)
Number of moles of Mg(OH)2 = 8.00 g/58 g/mol = 0.138 moles
Number of moles of HNO3 = 0.205 M × 24.2 mL/1000 = 0.00496 moles
Given that;
2 moles of HNO3 reacts with 1 mole of Mg(OH)2
0.00496 moles of HNO3 reacts with 0.00496 moles × 1 mole /2 moles = 0.00248 moles of Mg(OH)2
Hence, Mg(OH)2 is the reactant in excess.
The amount of Mg(OH)2 remaining = Amount present - Amount reacted
Hence; 0.138 moles - 0.00248 moles = 0.136 moles of Mg(OH)2
Learn more: https://brainly.com/question/9743981
since we cannot measure to absolute zero, how can we determine what the volume will be at that temperature?
Answer:
We can measure volumes approaching absolute zero and then predict what the volume would be at absolute zero.
Since there is NO molecular motion at absolute zero, the volume of a balloon at absolute zero should be zero.
If you headed to the deepest recesses of intergalactic space, shielded from starlight, the only thing that would heat you up would be the Big Bang's leftover glow: the cosmic microwave background at 2olume.ht v725 K. At that temperature, the balloon would have a volume.
Charles' Law asserts that a gas's volume (V) and temperature (T), which must be expressed in Kelvin, are directly proportional to one another. A change in temperature of one Kelvin unit corresponds to a change in one Celsius degree. Never forget that the value 0 on the Kelvin scale corresponds to -273 or "Absolute Zero."
What will the volume be at absolute zero, and how can we calculate it?Charles's Law, V = a T+ b, is used to calculate absolute zero once the mass measurements are transformed to high and low temperature gas volumes.
The volume of an ideal gas would theoretically be 0 at absolute zero, and there would be no more molecular motion. Actually, above this temperature, all gases condense into solids or liquids.
According to Boyle's Law, gas volume grows as pressure lowers. Charles' Law states that when the temperature rises, the volume of the gas increases.
Gases compress infinitely as the temperature is lowered because there is a linear relationship between temperature and pressure for the majority of gases (see gas laws). The volume of an ideal gas would theoretically be 0 at absolute zero, and there would be no more molecular motion.
To Learn more About Absolute Zero, Refer:
https://brainly.com/question/1191114
#SPJ2
The graph of an object's position over time is a horizontal line and y is not equal to 0. What must be true about the object's motion?(1 point)
o The acceleration is constant and non-zero.
o The velocity is constant and non-zero.
o The velocity is zero.
o The acceleration is negative.
Answer:
The velocity is zero
The interpretation of a position-time graph is required.
The correct option is The velocity is zero.
In a position time graph the y axis denotes the position and x axis denotes the time.
A horizontal line where [tex]y\neq 0[/tex].
This means that the points of the line will be for some value of x, the y value will always be constant.
The slope of a position-time graph will gives the velocity of the object.
Slope is given by
[tex]m=\dfrac{\Delta y}{\Delta x}[/tex]
Here, since the graph is a horizontal line, [tex]\Delta y=0[/tex]
[tex]\Rightarrow m=\dfrac{0}{\Delta x}=0[/tex]
The velocity of the person will be zero.
Learn more:
https://brainly.com/question/13693087
https://brainly.com/question/11290689
Magnesium has an atomic (proton) number of 12 and a mass number of 24.
How many magnesium atoms are there in 2 moles of magnesium? HELPPPPP
Answer:
1.2044x10^24 atoms
Explanation:
one mole of any element has 6.022x10^23 atoms
so 2 moles is just multiplying avogadros number by 2
2 x ( 6.022x10^23)= 1.2044x10^24 atoms
What form do ionic compounds take when solid?
Answer:
lattices
Explanation:
Ionic compounds are crystalline solids under normal conditions, have high melting points, and form lattices at the macroscopic level. Almost all of these solids dissolve in water and conduct electricity when dissolved. These substances are known as electrolytes because they can conduct electricity when in solution.
hope this helps
what type of solute causes the hydrogen ion concentration of a solution to decrease, which results in a high ph value?
Answer:
basic
Explanation:
like water to an acid or na2co3 or even diluting an acid causes its ph to increase
Helpppppppppppppppppppp
Answer:
option B it was captured by earth's gravity
Explanation:
please Brinlmark me please
What is it like on Mars? Please type 6 good answers.
Someone pls help me I will make you brain
Greenhouse gases such as N2O, CO2 and CH4 absorb heat. However, CH4 absorbs more heat than CO2 hence its emission must be controlled.
Green house gases are gases that when released into the atmosphere, can absorb infrared radiation and prevent it from escaping into outer space. This causes the temperature of the earth to increase steadily. Lately, the concentration of the greenhouse gases in the atmosphere has increased owing to anthropogenic activities such as burning of fossil fuels.
Green house gases include; N2O, CO2, CH4 etc. However, CH4 is capable of absorbing even greater heat than CO2. This makes it even more imperative to control the emission of methane gas.
Learn more: https://brainly.com/question/13721588
which type of control agent exerts noncompetitive inhibition?
Answer:
D
Explanation:
If your choices are:
a) Substrate analog
b) Protein kinase
c) Allosteric effector
d) Both (b) and (c).
then your answer is D :)
Name any two metals that are found in liquid state at NTP.
Answer:
mercury and gallium are two metals that are found in liquid state at NTP.
molecular formula of sulphur trioxide by criss cross method
Answer:
Sulfur trioxide: SO3.
Explanation:
How I came to this conclusion:
I noticed that the compound consists of non-metals, therefore it must be a covalent compound -
meaning I use prefixes for compounds.
Sulfur is S. Simple enough. Trioxide has the prefix of tri, meaning "3". Therefore there is 3 atoms of oxygen. Combine them and I get SO3.
Don't be confused with sulfite: (SO3)2− and sulfate: (SO4)2−
What is the molarity of 930 mL of LiCl solution that contains 139.9 g of LiCl?
O A. 3.5 mol/L
O B. 150 mol/L
hipotle and like
O C. 3.3 mol/L
O D. 3.5 x 10-3 mol/L
Answer:
3.5 mol/L
Explanation:
First convert the 139.9g of LiCl into moles of LiCl. Don't do the sig fig rule until the very end.
Second, take 930mL of LiCl and divide it by 1000 to convert it to liters.
Third use the molarity formula which is M=mol/L and divide 0.930L by 3.300773877mol and you will get 3.549219223. This is where the sig fig rule will come into play. 3.5mol/L is a reasonable answer for this problem.
Why can groundwater only collect in rock that is porous?
Porous rock has gaps between rock particles that can fill with water.
Porous rock contains different-sized particles.
Porous rock is made of certain types of rock that attract water molecules.
Porous rock contains particles that are very close together.
Answer: Porous rock has gaps between rock particles that can fill with water. but i’m not 100% sure
Explanation:
Answer:
porous rock has gap between rock particles that can fill with water
what quantities vary between isotopes of an element
The quantities that vary in the isotopes of the same element is number of nucleons and the number of neutrons.
Isotopes are atoms of the same element that have different numbers of neutrons. The number of protons and electrons in isotopes of an element remains the same because they determine the element's chemical properties.
Nucleons refers to the collective number of protons and the neutrons present inside the nucleus. Isotopes can have different physical properties due to the varying number of neutrons.
Therefore, the isotopes differ in the quantity of number of neutrons and the nucleons present.
To know more about nucleons, visit:
https://brainly.com/question/34136361
#SPJ3
Convert 4.36 x 10 square 25 molecules of CH3OH to moles.
Answer:
72.43 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{4.36 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 72.425249[/tex]
We have the final answer as
72.43 molesHope this helps you
Which of the following is a physical property of matter
Answer: Physical properties of matter include color, hardness, malleability, solubility, electrical conductivity, density, melting point, and boiling point. For the elements, color does not vary much from one element to the next
Answer:
Physical properties of matter include;
evaporationcondensationsublimationfreezingmelting…and so on[tex].[/tex]
How many moles of hydrogen gas would be required to produce 25 moles of H2O?
The balanced equation for the production of water from hydrogen gas is
2H₂ + O₂ → 2H₂O
Based on the balanced equation, for every mole of hydrogen, a mole of water is produced.
∴ Since the moles of water = 25 moles
then the moles of hydrogen gas = 25 moles25 moles of H₂ (hydrogen gas) are required to make 25 moles of H₂O.
What is Stoichiometry ?Stoichiometry is an important concept which helps us use the balanced chemical equation to measures the amount of reactants and products.
What is Balanced Chemical Equation ?The balanced chemical equation is the equation in which the number of atoms on the left hand side that is reactant side is equal to the number of atoms on the right hand side that is product side in an equation.
First we have to write the Balanced chemical equation
2H₂ + O₂ → 2H₂O
To produce 2 moles of water, 2 moles of hydrogen are required to produce 25 moles of water.
According to the Stoichiometry
[tex]\frac{2\ \text{moles of}\ H_2}{2\ \text{moles of}\ H_2O} \times 25\ \text{moles of}\ H_2O[/tex]
= 25 moles of hydrogen gas is required
Thus, from above conclusion we can say that 25 moles of H₂ (hydrogen gas) are required to make 25 moles of H₂O.
Learn more about the Stoichiometry here: brainly.com/question/14935523
#SPJ2
If you have 24.19 moles of nickel, how many atoms do you have?
Answer:
No idea
Explanation:
I'll tell u how to do it. You multiply by amidagros number. that is how many atoms you have. Your welcome.