Answer:
See explanation
Explanation:
Even though the options were not stated in the question, it is clear that the prediction required must reflect the stated fact that the sublimation temperature of CO2 is -78.5°C. This is the fact that was observed in the cause of the experiment. Hence any of the options that reflects this statement must be the correct option among the list of options available in the question.
What is the scientific method and what the second step of the scientific ? If you answer the question right you will get a 5 star and a brainly
Answer:
a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.The basic steps of the scientific method are: 1) make an observation that describes a problem, 2) create a hypothesis, 3) test the hypothesis, and 4) draw conclusions and refine the hypothesis.
Explanation:
the scienticif Method and the second step of the scientific
(d) why does the h3o concentration have more influence on the precipitation of the salt of a weak acid, such as cac2o4(s), than on the precipitation of the salt of a strong acid, such as agcl(s) or caso4(s)?
Answer:
See explanation
Explanation:
When we are comparing the effect of H3O^+ on the precipitation of a salt of a weak acid such as CaC2O4(s) and that of a strong acid such as AgCl(s) or CaSO4(s), we discover that H3O^+ has more effect on the precipitation of the salt of a weak acid.
This is because, anions of the weak acid combine with H^+ from H3O^+ thereby decreasing the concentration of the anion of the salt of the weak acid and increasing the solubility of the precipitate.
Separate a mixture of sand, common salt, copper pieces and iron fillings. Also measure the amount of common salt in the mixture. Write the steps and the procedure of separation. Also what safety measures you will take during the experiment.
Answer:
Explanation:
This question seeks to test the knowledge of separation techniques.
From the narration in the question, the first separation to be done is the removal of Iron fillings by the use of magnet (magnetic separation). Since Iron is magnetic, the iron fillings will be attracted by the magnet hence removing the iron fillings from the mixture.
The second constituent to be removed will be the copper pieces by the use of a sieve (sieving). Copper pieces have relatively larger sizes than sand and common salt, hence a sieve (which separates particles based on size) can be used to remove the copper pieces from the mixture.
What will be left in the mixture after the processes above will be salt and water. This mixture will have to be dissolved in water; the salt will dissolve in water while the sand will not. After which, filtration will be done to remove the sand which will be collected on the filter paper as filtride and the salt solution will pass through the filter paper as filtrate.
The salt solution can then be evaporated to dryness to retrieve the solid salt from the solution.
The amount of salt in the mixture can then be measured using a weighing balance.
Some of safety measures to be taken during the course of this experiment includes performing the experiment in an airtight and controlled environment. Lab coat and hand gloves should be worn during the course of the experiment. The evaporation to dryness should not be done close to an inflammable material/substance
How are solid , liquid and gas different in volume and mass?
Answer:
Explanation:
Solids have a fixed shape and occupy a fixed volume. because the particles in liquid are so close together,liquids do'not easily compress,so their volume is fixed. gases can also flow, so they occupy the shape of the whole container.
A piece of metal ore weighs 9.00 g. When a student places it into a graduated cylinder containing water, the liquid level rises from 21.25 mL to 26.47 mL. What is the density of the ore
Answer:
1.72 g/ml
Explanation:
If our aim is to determine the density of the metal ore, then;
Mass of the metal ore= 9.00 g
Volume of the ore= volume of water displaced = 26.47 - 21.25 = 5.22 ml
Density of the ore= 9.00 g/5.22 mk
Density of the ore= 1.72 g/ml
n 1606, money to establish the colony of Jamestown was raised by
Aluminum has a density of 2.70 g/cubic cm . What would be the mass of a 10.0 cubic centimeter sample?
Answer:
27g.
Explanation:
M = D x V
M = 2.7 x 10
M = 27.
______Reflects how closely packed the particles of matter are
Answer:
Density
Explanation:
Complete the structure of poly propane in the equation.
n propene molecules == polymer (polypropene)
Helium is an odorless, colorless gas at room temperature. It is less dense than air. That's why helium balloons float. It is a non-reactive gas, a member of the Noble gas family. Its melting point is -272.2 oC and its boiling point is -268.93 o A chemical property of Helium is?
Answer:
Non-flammable It is the only element that doesn't solidify under ordinary pressure and remains a liquid enven at absolute zero. When it electricity runs through helium it glows a pale peach color.A scientist is researching the solar system. How can the scientist best add to existing empirical evidence about the solar system? a. The scientist can debate the research with other scientists. b. The scientist can develop a new law regarding the solar system. c. The scientist can make and record observations. d. The scientist can write an opinion column about the researc
Answer:
The correct option is;
c. The scientist can make and record observations
Explanation:
Empirical evidence are evidences obtained by direct observation, sensual perception or direct measurement. It is the processed and useful data gathered and stored in a material form or documented to provide record of the measurement.
With the aid of empirical evidence, it is possible for researchers to find answers to question regarding topics that can vastly impact every day life.
With empirical evidence, it is possible to determine the effects of treatment in a study such as the invention of working car safety devices such as seat belts and airbags.
Several scientists from different countries are asked to examine the results of an experiment before a journal will print it.
Which term best describes this step of the investigative process?
A)question
B)communication of results
C)peer review
D)experiment control
Answer:
C)peer review
Explanation:
Peer review involves the evaluation of scientific research work by other professionals working in the same field. It is one of the stages a manuscript passes through before it is published in any reputable journal.
Peer review is important because it ensures that only high quality and original scientific research is published for the consumption of other professionals in the same field.
Which of the following is an oxidation-reduction reaction? KOH + HNO3 → H2O + KNO3 CaCl2 + Na2SO4 → CaSO4 + 2NaCl AgNO3 + NaCl → AgCl + NaNO3 Al2(SO4) 3 + 6KOH → 2Al(OH)3 + 3K2SO4 N2 + O2 → 2NO
Answer:
N2 + O2 → 2NO is an oxidation-reduction reaction.
Explanation:
An oxidation-reduction reaction (also know as Redox reaction) is a type of chemical reaction that involves a transfer of electrons between two species. It occurs when the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron.
We will consider the equations one after the other.
KOH + HNO3 → H2O + KNO3Oxidation numbers of the individual element on the reactant side:
KOH : K = +1, O = -2, H = +1
HNO3 : H = +1, N = +5, O = -2
Oxidation numbers of the individual element on the product side:
H2O: H = +1, O = -2
KNO3: K = +1, N = +5, O = -2
There is no change in the oxidation numbers, hence, it is not an oxidation-reduction reaction.
CaCl2 + Na2SO4 → CaSO4 + 2NaClOxidation numbers of the individual element on the reactant side:
CaCl2 : Ca = +2, Cl = -1
Na2SO4: Na = +1, S = +6, O = -2
Oxidation numbers of the individual element on the product side:
CaSO4: Ca = +2, S = +6, O = -2
NaCl: Na = +1, Cl = -1
There is no change in the oxidation numbers, hence, it is not an oxidation-reduction reaction.
AgNO3 + NaCl → AgCl + NaNO3Oxidation numbers of the individual element on the reactant side:
AgNO3: Ag = +1, N = +5, O = -2
NaCl: Na = +1, Cl = -1
Oxidation numbers of the individual element on the product side:
AgCl: Ag = +1, Cl = -1
NaNO3: Na: +1, N = +5, O = -2
There is no change in the oxidation numbers, hence, it is not an oxidation-reduction reaction.
Al2(SO4) 3 + 6KOH → 2Al(OH)3 + 3K2SO4Oxidation numbers of the individual element on the reactant side:
Al2(SO4)3: Al =+3, S = +6, O = -2
KOH: K = +1, O = -2, H = +1
Oxidation numbers of the individual element on the product side:
Al(OH)3: Al =+3, O = -2, H = +1
K2SO4: K = +1, S = +6, O = -2
There is no change in the oxidation numbers, hence, it is not an oxidation-reduction reaction.
N2 + O2 → 2NOOxidation numbers of the individual element on the reactant side:
N2: N = 0
O2: O = 0
Oxidation numbers of the individual element on the product side:
NO: N = +2, O = -2
There are changes in the oxidation numbers, hence, it is an oxidation-reduction reaction.
The following is an oxidation-reduction reaction - N2 + O2 → 2NO
Oxidation numbers represent the potential charge of an atom in its ionic state. If the oxidation number decreases in a reaction, it is reduced. If an atom's oxidation number increases, it is oxidized.
CaCl2 + Na2SO4 → CaSO4 + 2NaCl is a double displacement reaction KOH + HNO3 → H2O + KNO3 is acid-base neutralization reaction AgNO3 + NaCl → AgCl + NaNO3 is double displacement reaction Al2(SO4) 3 + 6KOH → 2Al(OH)3 + 3K2SO4 is double displacement reactionAll three reaction mention above is not oxidation-reduction reaction as each atom has the same oxidation number in these reactions. N2 + O2 → 2NO is oxidation-reduction reaction.= > Oxidation state of N in the reactant is 0
=> Oxidation state of N in the product is +2
So, N is oxidized
=> Oxidation state of O in the reactant is 0
=> Oxidation state of O in the product is -2
So, O is reduced
Thus, the following is an oxidation-reduction reaction - N2 + O2 → 2NO
Learn more:
https://brainly.com/question/11672211
Why is it important to read over the SDS sheet before you do a lab?
Answer:
so you know what to do and you know the rules
Explanation:
A human is an example of a(n)
A) element
B) compound
C) homogeneous mixture
D) heterogeneous mixture
Answer:
d
Explanation:
'Heterogeneous Mixture' is characterized as 'a mixture that has more than one phase and its components are distinct visibly.'
The human being serves as an illustration of:
D). heterogeneous mixture
The components of a heterogeneous mixture are not distributed uniformly leading to their visibility. Humans demonstrate a 'heterogeneous mixture' as the human body is comprised of distinct elements and not divided uniformly. Some parts are hard, while the others are soft. Some comprising of calcium, phosphorous while the others are formed of carbon and nitrogen. The tendons, blood vessels, hemoglobin, cartilage etc., all possess a varied composition with uneven distribution.Thus, option D is the correct answer.Learn more about 'heterogeneous' more:
brainly.com/question/5924138
Please help me with this questions.
Define compressibility
Answer:
Compressibility means: being able to basically squish something easier. Like water, water can be reduced in volume or size under pressure When that water expands, it turns into a gas.
Explanation:
Sea la reacción de síntesis de la urea: 2 NH3 + CO2 → (NH2)2CO + H2O Si tenemos 500 gramos de NH3 y 1000 gramos de CO2 calcular cuál es el reactivo limitante y la cantidad de urea producida.
Answer:
El reactivo limite es [tex]NH_3[/tex] y la cantidad de urea producida es 881.58 g
Explanation:
Podemos empezar con la reacción:
[tex]2NH_3~+~CO_2~->~(NH_2)_2CO~+~H_2O[/tex]
Tenemos 2 átomos de nitrógeno en ambos lados, 1 átomo de carbono en ambos lados, 2 átomos de oxigeno en ambos lados y 6 átomos de hidrógeno en ambos lados. Por lo tanto la reacción esta balanceada.
Ahora, para hallar el reactivo limite necesitamos seguir los siguientes pasos:
1) Convertir a moles usando la masa molecular de cada compuesto ( 17 g/mol para el amoniaco y 28 g/mol para el dióxido de carbono).
2) Usando el la relación molar entre cada compuesto con la urea podemos calcular las moles de urea ( para el amoniaco la relación es 2:1 y para el dióxido de carbono la relación es 1:1).
3) Finalmente, usando la masa molar de la urea (60 g/mol) podemos calcular la masa de urea.
[tex]500~g~NH_3\frac{1~mol~NH_3}{17~g~NH_3}\frac{1~mol~(NH_2)_2CO}{2~mol~NH_3}\frac{60~g~(NH_2)_2CO}{1~mol~(NH_2)_2CO}=881.58~g~(NH_2)_2CO[/tex]
[tex]1000~g~CO_2\frac{1~mol~CO_2}{28~g~CO_2}\frac{1~mol~(NH_2)_2CO}{1~mol~CO_2}\frac{60~g~(NH_2)_2CO}{1~mol~(NH_2)_2CO}=1364.6~g~(NH_2)_2CO[/tex]
El elemento que tiene la menor cantidad de urea se da en el calculo del amoniaco. Por lo tanto, el reactivo limite es el amoniaco y la cantidad de urea producida es 881.58 g
Espero que sea de ayuda!
How do I convert 125000g to scientific notation?
why are viruses considered as being at the 'borderline' between living and non-living things?
Answer:
Viruses are considered at the borderline of living and non-living because they show both the characteristics of living and a non-living. As they react like non-living in the free atmosphere but when they enter the body of a living organism then they show the features of a living organism and start reproduction.
Answer:
because they become living inside the body of living organisms.
Explanation:
their body is composed of only DNA/RNA enclosed in protein capsule. they use host's DNA to replicate their own DNA/RNA. the below diagram is structure of RNA bacteriophage virus
After completing an experiment, all chemical wastes should be an disposed of according to your instructor’s directions. be left at your lab station for the next class. c dumped in the sink. d taken home.
Answer:1
Explanation:
Answer: c
Explanation:
Disposed of.... etc.
Which of these are properties of solids? Select all that apply.
a. Takes the shape of its container.
b. Molecules vibrate in a fixed position.
c. Strong attraction between molecules.
d. No definite volume.
PLEASE HELP
Answer:
B.
Explanation:
Solids vibrate in a fixed position because they keep their shape. Liquids take the shape of their container, so A cannot be the answer. Solids do have a definite volume, so D is not your answer.
(1.500x10^3)x(3.50x10^5)=
Answer:
525000000
Explanation:
[tex]1.500 \times {10}^{3} = 1500 \\ 3.50 \times {10}^{5 } = 350000 \\ 1500 + 350000 = 525000000[/tex]
Abby fills a graduated cylinder with 3 mL of water. She
then drops a small rock into the cylinder, and the water
level rises to the 5 mL mark. What is the volume of the
rock?
Answer:
Volume of the rock, V = 2 mL
Explanation:
It is given that,
Water filled in a graduated cylinder is 3 mL
She then drops a small rock into the cylinder and the water level rises to the 5 mL mark
We need to find the volume of the rock.
The volume of the rock is equal to the difference in volume mark. So,
V = 5 mL - 3 mL
V = 2 mL.
20 points! So I got this lab report to do and I need some more info it's about lab safety got any info I can use! :) If so, Thank you!
HELPPPPP ME ASAP I'll give you a thanks and mark you as brainliest and give u points
Suppose that the clay balls model the growth of a planetesimal at various stages during its accretion. Choose the planetesimal that is most likely to pull in debris particle A.
Answer: 2nd one
Explanation:
PLATO
A student drew a diagram of the quantum model of an atom, as shown. A small circle is shown. Six light gray spheres and six dark gray spheres are shown inside the circle. On the outer side of the circle is a diffused shaded circular region. This diffused shaded circular region has two distinct bands of dark gray shading in it. Which of the following explains if the student's diagram is correct or incorrect? The diagram is incorrect because electrons follow orbital rings around the nucleus. The diagram is incorrect because there is only a single type of particle at the center of the atom. The diagram is correct because electrons are present in a negatively charged cloud outside the nucleus. The diagram is correct because all electrons can be accommodated in two electron clouds around the nucleus.
Answer:
The diagram is incorrect because there is only a single type of particle at the center of the atom.
Explanation:
The small circle at the centre of the sphere which contains six light gray spheres and six dark gray spheres represents the nucleus of the atom which is found at the centre of the atom.
The nucleus contains only one type of particle which is the proton. Hence the representation of two particles at the centre of the circle makes the model incorrect.
Answer:
D- The diagram is correct because all electrons can be accommodated in two electron clouds around the nucleus.
Explanation:
This is the correct answer because i just took the pre-quiz and tried B and A and they were both incorrect and C just doesnt make any sense so yeah hope it helped :)
How many meters are present in the 12.45 miles? Please show your work, and report your answer with the correct number of significant figures and appropriate units.
Explanation:
We know that,
1 mile = 1609.34 m
We need to find how many meters are present in the 12.45 miles. To find it use unitary method as follows :
12.45 mile = 1609.34 × 12.45
12.45 mile=20036.283 meters
or
[tex]12.45\ mile=2.0036\times 10^4\ m[/tex]
Hence, this is the required solution.
which of these particles are moved around when bonds are formed in order for the atom to become stable?
Answer:The two types of chemical bonds that atoms can form to achieve stability are called ionic bonds and covalent bonds. Does this help
Explanation:
Name the unit being abbreviated in each measurement (spelling counts). Only write the name of the unit, do not include the number. 0.8 L litre 3.6 cm centimeter 4.0 kg kilogram 3.5 s 373 K
Answer:
Litre (L) , Centimetre (cm) , Kilogram (Kg), Seconds (s) and Kelvin (K)
Explanation:
The units are used for the following measurement;
Litre = Volume
Centimetre = Length
Kilogram = Mass
Seconds = Time
Kelvin = Temperature