Answer: Significant figures in a measurement are all measured digits, and one estimated digit
Significant figures communicate the level of precision in measurements Significant figures are an indicator of the certainty in measurements.
Explanation:
Significant figures : The figures in a number which express the value or the magnitude of a quantity to a specific degree of accuracy or precision is known as significant digits.
The significant figures of a measured quantity are defined as all the digits known with certainty and the first uncertain or estimated digit.
Rules for significant figures:
1. Digits from 1 to 9 are always significant and have infinite number of significant figures.
2. All non-zero numbers are always significant.
3. All zero’s between integers are always significant.
4. All zero’s preceding the first integers are never significant.
5. All zero’s after the decimal point are always significant.
The true statements are
Significant figures in measurement are all measured digits, and one estimated digit
Significant figures communicate the level of precision in measurements Significant figures are an indicator of the certainty in measurements.
The following information should be considered:
The figures in a number that express the value or the magnitude of a quantity is known as significant digits.The significant figures of a measured quantity refers to all the digits known with certainty.Learn more: https://brainly.com/question/1979431?referrer=searchResults
What is the chemical name of the covalent compound P4O9? A. tetraphosphorus nonaoxygen B. tetraphosphate nonoxygen C. tetraphosphide nonaoxide D. tetraphosphorus nonoxides.
Answer: The chemical name of the covalent compound [tex]P_4O_9[/tex] is, tetraphosphorous nonaoxide.
Explanation:
A covalent compound is a compound where the sharing of electrons takes place between elements where both the elements are non-metals.
The naming of covalent compound is given by:
1. The less electronegative element is written first.
2. The more electronegative element is written second. Then a suffix is added with it. The suffix added is '-ide'.
3. If atoms of an element is greater than 1, then prefixes are added which are 'mono' for 1 atom, 'di' for 2 atoms, 'tri' for 3 atoms and so on.
Hence, the correct name for the compound [tex]P_4O_9[/tex] which is a covalent compound is, tetraphosphorous nonaoxide.
How are industrial and agricultural pollution similar?
Answer:
Both of them are polluting the environment. Industrial pollution is the pollution caused from industries and it can be in different forms such as water waster or air pollution. Agricultural pollution is caused from plants or crops that are grown by the farmers. For example, pesticides that may ruin the soil and is dangerous for our environment.
Explanation:
name two bases which react with dillute sulfuric acid to give zinc sulfate
Answer:
Zinc Carbonate
Zinc Nitrate
Explanation:
Someone please help me with the second question ONLY
Answer:
no
Explanation:
this experiment could not be replicated, because there are no specific measurements. the details would not be the same because it does not include the type of paper used nor the diameter, width or length. A guess of the measurements would be the only way to replicate this experiment but other then that, no you cannot.
What is the molarity of a solution that contains 6 moles of NaCl in 3 L of solution?
a
2.0 M
b
0.5 M
c
0.25 M
d
18.0 M
Answer:
a
2.0 M
Explanation:
divide 6by 3
formula : molarity=moles divided by volume of solutions
which of these methods could are used to separate an insoluble solid and soluble solid
Answer:
To separate an insoluble solid from a soluble solid: Mixing the mixture with water, filtering out the insoluble solid, and then evaporating the water to isolate the soluble solid.
Explanation:
Answer:
Mixing the mixture with water, filtering out the insoluble solid, and then evaporating the water to isolate the soluble solid
How much cesium (half-life = 2 years) would remain from a 10 g sample after
4 years?
O A. Og
OB. 8g
O c. 59
O D. 29
SUBMIT
Answer: 2.5 grams
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) to calculate the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{2years}=0.346years^{-1}[/tex]
b) to find amount left after 4 years
[tex]4=\frac{2.303}{0.346}\log\frac{10}{a-x}[/tex]
[tex](a-x)=2.5g[/tex]
Thus 2.5 g of cesium would remain from a 10 g sample after 4 years
explain why we must balance all chemical equations
Answer:
The chemical equation needs to be balanced so that it follows the law of conservation of mass.
Explanation:
Explanation:
the chemical equation needs to be balance so that it follows the law of conservation of mass. a balance chemical equation occurs when the number of the different atoms of elements to the reactants side is equal to that of the product side. balancing chemical equation is a process of trial and error .
Both E. coli and Salmonella are single-celled organisms. They do not have a nucleus or other membrane-bound organelles. Based on the concept of domains, what do they have in common? They both belong to kingdom Fungi. They both belong to domain Eukarya. They both belong to domain Bacteria. They both belong to kingdom Animalia.
Answer:
domain bacteria
Explanation:
Salmonella and E. coli are same in the sense that they are both bacteria,
Answer:
B
Explanation:
Calculate the number of moles of MgO if the mass of MgO (magnesium oxide) is 50 g?
Please help... I will mark the answer with brainlist...
Answer:
1.24mol
Explanation:
m(MgO)=50g
molar mass=40.30g/mol (i search in google coz dosnt have book)
n=mass/molar mass
=50/40.30
=1.24mol
Please help!! This is for chem!!!
Answer:
1st answer choice
P4O6 + 2 O2 -> P4O10
Explanation:
You need to cancel out reactants and products that are the same.
P4 cancels out because it appears in both reactants and products
We get 2 O2 in the reactants because 5-3= 2
Thus, answer choice 1 is correct.
H3PO4 + Ca(OH)2 → Ca(H2PO4)2 + H2O
Given question is incomplete. The complete question is as follows.
Balance the following equation:
[tex]H_3PO_4 + Ca(OH)_2 \rightarrow Ca(H_2PO_4)_2 + H_2O[/tex]
Answer: The balanced chemical equation is as follows.
[tex]2H_3PO_4 + Ca(OH)_2 \rightarrow Ca(H_2PO_4)_2 + 2H_2O[/tex]
Explanation:
When a chemical equation contains same number of atoms on both reactant and product side then this equation is known as balanced equation.
For example, [tex]H_3PO_4 + Ca(OH)_2 \rightarrow Ca(H_2PO_4)_2 + H_2O[/tex]
Number of atoms on reactant side:
H = 5
P = 1
O = 6
Ca = 1
Number of atoms on product side:
H = 6
P = 2
O = 9
Ca = 1
In order to balance this equation, we will multiply [tex]H_3PO_4[/tex] by 2 on reactant side and we will multiply [tex]H_2O[/tex] by 2 on product side. Hence, the balanced chemical equation is as follows.
[tex]2H_3PO_4 + Ca(OH)_2 \rightarrow Ca(H_2PO_4)_2 + 2H_2O[/tex]
In a science experiment, 10 tomato plants were given fertilizer in their water each week and 10 tomato plants were given plain water each week. All other factors were the same for all plants. At the end of each week, the height of each plant was measured. What was the independent and dependent in the experiment?
1. the height of the plant
2. the amount of water given
3. the type of plant
4. whether or not there was fertilizer in the water
Answer:
Independent: whether or not there was fertilizer in water
Dependent: height of plants
Explanation:
In an experiment, there is an independent and a dependent variable. The independent variable is what is changed in the experiment. The dependent variable is what is measured.
In this experiment, 10 tomato plants are given fertilizer in the water, while 10 other tomato plants are given regular water. Everything else is kept constant, and the heights are measured at the end of the week.
The independent variable is what is being changed. In this experiment, the only thing being manipulated is the fertilizer. One group of the plants is given fertilizer, while the other is not. Therefore, the independent variable is whether or not there was fertilizer in the water.
The dependent variable is what is being measured. In this experiment, the thing that is being measured is the height of the plants. Therefore, the dependent variable is the height of the plants.
Why would cooking equipment be responsible for more total fires but smoking smoking responsible for more fire deaths?
Answer:
For the last few decades fires started by any type of smoking material has been the number one leading cause for household fire fatalities. It could just be that people luckily escape in time with cooking equipment fires, and smoking related fires just result in more deaths.
Which of the following correctly describes a Brønsted-Lowry base? A. It accepts protons. B. It donates protons. C. It produces OH− ions in solution. D. It donates an electron pair.
Neutral atoms & charged atoms has
equal number of electrons
Answer:
wrong.
Explanation: charged atoms have have more electrons than neural because they charge it . a neural atom has eaqual number of electrons and neutrons.
hope this helps(^人^)
Which balanced equation represents an oxidation-reduction reaction?
Answer:
Oxidation states are used in chemistry solutions. It is a bond in which electron transfers easily from one nucleus to another nucleus.
Explanation:
Oxidation-reduction reactions have some rules.The oxidation state is 0 at an uncombined bond.The bond of oxidation reduction is +1 in alkeli metal. The bond in two metal is +2The oxidation reduction state at helogens is -1. It does not happened always.The oxygen bond in oxidation and reduction is -2. The sum of the oxidation state is equal to the compound charges.In this process the changes occur for any elements. Redox could be occur. Its oxidized and reduction reaction can be seen in this process.How do forces between particles in solids compare to forces in the other
states of matter?
O A. The forces in solids are stronger than forces in liquids and gases.
O B. The forces in solids are weaker than forces in liquids and gases.
O C. The forces in solids are stronger than forces in liquids but weaker
than forces in gases.
D. The forces in solids are weaker than forces in liquids but stronger
than forces in gases.
Answer:
the answer is A
Explanation:
Forces are the intermolecular interaction between the matter. Forces present in a solid are strongest. Thus, option A is correct.
What are the phases of matter?The matter is any substance that occupies a volume. Matter can be a solid, gas, or liquid. The solid phase particles are tightly closed to each other making the force strong.
The particles of liquids that are not too compact are a little free and in gases, the particles are very free, which makes the bonding and the force the weakest.
Therefore, option A. the solids have the strongest intermolecular bonding.
Learn more about intermolecular forces here:
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Which structure below contains all of the others?
DNA
gene
chromosome
nucleus
Answer:
nucleus
Explanation:
The nucleus holds all the other things, keeping them safe and confined.
Answer:
Nucleus
Explanation:
It contains DNA which contains a GENE which contains a CHROMOSOME so its NUCLEUS
1. Calculate the pH of a 0.35 mol/L solution of ammonia.
Answer:
Explanation:
NH3 + H2O ⇌ NH4 + OH-
0.35 0.35
-log[OH-] = -log0.35 = 0.46 = pOH
14 - 0.46 = 13.54 = pH
How are ironic bonds and covalent bonds different and how are they different?
Which factor affects gravitational potential energy but not elastic potential energy?
Answer:
spring constant. acceleration due to gravity. distance from a given position. amount of matter in the object.
Explanation:
hope this helps you :)
Answer:
spring constant
Explanation:
What is the pH of a 6.4x10^-10 m OH- solutions
Answer:
pH: 4.80617997398
pOH: 9.19382002602
[H+]: 1.5625E-05
[OH-]: 6.4E-10
ACID
Hope it helps :)
Why does the weight of the dry ice go down while it’s sitting on the scale
Dry ice is colder, heavier, less messy than regular ice. If I understood your question correctly, the mass of it would decrease bc it is being dispersed into the air as carbon dioxide.
Explanation:
As a result of the transformation of solid carbon dioxide into carbon dioxide gas, which enters the atmosphere, the weight of the ice decreases and falls.
What is Melting?Melting, also known as fusion, is a physical process that causes a substance's phase transition from solid to liquid. This happens when the internal energy of a solid increases, typically through the application of heat or pressure, which raises the temperature of the substance to the melting point. Melting is the transformation of a solid into a liquid caused by the application of heat. In a pure crystalline solid, this process occurs at a fixed temperature known as the melting point; an impure solid usually melts over a range of temperatures below the melting point of the principal component.The melting point of a solid is the temperature at which melting occurs. In this process, heat is released from the solid.To learn more about Melting refer to:
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CHEM HELP PLEASE
a reaction that has been calculated to produce 346 g of CH3OH actually produced 312 g of CH3OH. what is it's percent yield?
Answer:
90.2%
Explanation:
% yield = actual yield/ theoretical yield * 100%
% yield = (312/346)*100% = 90.2%
The three states of matter can be arranged in the increasing order of interparticle forces as 1) gas > liquid >solid 2) solid >liquid > gas 3) liquid > gas > solid pls answer fast
Answer:
OPTION 2 SOLID>LIQUID>GAS
Explanation:
because the inter molecular forces are the strongest in the solid than in liquid and than in gas
Why do scientists consider humans to be "carbon creatures"?
PLEASE HELP ME
Answer:
Scientists consider human to be" carbon creatures" because carbon atoms form the backbone or foundation of pretty much the essential biological molecules floating around in our bodies (except water, of course.) All in all, scientists can consider humans to be " carbon creatures" because our skin, hair and cells are all made out of molecules that contain huge amounts of carbon.
Hope this helps! God bless!
What is the net ionic equation of
Mg(s) + Zn2+ + 2NO3 → Mg2+ + 2NO3 + Zn(s)?
A. Mg(s) → Zn(s)
B. Mg(s) + Zn2+ → Mg2+ + Zn(s)
C. Mg(NO3)2 + Zn(s) → Zn2+ + 2NO3 + Mg(s)
D. Mg(s) + Zn(NO3)2 (aq) → Mg(NO3)2(aq) + Zn(s)
Answer:
Mg(s)+Zn2+>>>>>Mg2++Zn(s) B
Explanation:
The net ionice quation of a reaction represents the net change in the reaction.Here the reaction proceeds to the formation of Mg²⁺ ion and metallic zinc. Thus option B is correct.
What is ionic equation?
A balanced equation of chemical reaction represents the perfect stoichiometric ratio of each reactants and products where each elements have to be equal in number in both side.
An ionic equation represents the ions involved in the reaction and the charges and coefficients of ions have to balanced each side.
In the electrolysis of magnesium and zinc electrodes, metallic magnesium oxidizes to Mg²⁺ions and Zn²⁺ ions reduces to metallic zinc. The NO³⁻- ions remains as same as in its aqueous state in the electrolyte.
Hence the net ionic equation is as written in option B.
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Identify what is in that photo please!! (10 pts)
Answer:
Electromagnet
Explanation:
Which of these pulls denser rocks towards Earth's center?
1.thermal energy
2.gravity
3.radiation
Answer:
Gravity pulls denser rocks down toward Earth's center. This causes less dense rocks and magma to move upward toward the surface.
Answer:
Gravity boo
Explanation: