Answer:
B. Beryllium
Explanation:
because the trend of ionization is going up a group it increases, as going across a period it deceases. beryllium being closes to the hist point in the periodic table it has the highest ionization energy. hope this helps.
Answer: B. Beryllium
Explanation: Apex
What are some possible sources of error in a titration experiment? Share some tips to minimize errors with your classmates.
Answer:
1. by not avoiding air bubbles from being trapped in the burette or pipette when filling them
2. not cross-checking the burette if it's slanted or vertically clamped
3. forgetting to rinse the pipette or burette with the solution to be used
4. not considering to take readings from the bottom of the meniscus with the eye level
5. finally, adding more than three drops of indicators to the pipetted solution
Explanation:
1. because the air bubbles will be mistakenly considered as part of the amount of the solution taken instead of that actually used up, and a higher titre value would be obtained
2. because if it's slanted, the acid level will be titled to one side and wrong reading will be recorded
3. rinsing to avoid diluting the acid or base with water that wets the burette or pipette
4. to avoid error of parallax and helps you to obtain accurate readings
5. excess burette solution than would normally have been consumed would be used up to change the colour of the indicator
Titration has been defined as the neutralization reaction for the acid and base, resulting in the formation of salt and water. It has been used for the determination of strength of acid and base.
The general source of error in titration has been;
The measurement of volume in burette by at the lower meniscus. It has been corrected with the application of measurement at eye level.The air bubble in the burette results in the incorrect measurement of the volume of burette. It can be corrected by tapping the burette or by slowing adding the solution to remove the bubble.The absence of rinsing the burette before use has been resulted in the water droplets that has been results in the incorrect measurement and dilution of the solution. The correction has been made by the use of dried burette.The titration error has generally being manual error, and can be easily corrected.
For more information about titration, refer to the link:
https://brainly.com/question/24704707
Which method of moving materials in and out of a cell requires energy?
active transport
passive transport
osmosis
diffusion
Answer:
Active Transport
Explanation:
As the name suggests, in active transport you need energy to move materials in and out. Similar to how if you want to be active you need energy, same goes with movements in our cells as well.
What's the molarity of the solution containing 10 g of NaCN in 250 mL of solution?
Answer:
0.816
Explanation:
1 mole of NaCN is
Na = 23
C = 12
N = 14
Total = 49 grams / mole (just add 23 + 12 + 14)
moles when only 10 grams of NaCN are used.
moles = grams/molar mass
grams = 10
molar mass = 49
moles = 10 / 49
moles = 0.204 moles
Volume in Liters
250 mL = 250mL/1000 mL / Liter = 0.25 Liters
Molarity
M = m/V
M = 0.204/0.25 = 0.816
Which is the correct skeleton equation for water + sodium sod hydroxide + hydrogen ?
Answer:
H₂O + Na → NaOH + H₂
Explanation:
Firstly, a skeleton equation does not reflect the relative amount of reactants and products. A skeleton reaction only identifies the reactant and product by their chemical formula but it does not quantify them. A skeleton chemical equation is simply described as an unbalanced equation.
The question asked for the correct skeleton reaction of water and sodium to produce sodium hydroxide and hydrogen.
Let us represent them with their chemical formula
Water → H₂O
Sodium → Na
Sodium hydroxide → NaOH
Hydrogen → H₂
The skeleton reaction will be
H₂O + Na → NaOH + H₂
if a car of 2 kg mass has a force of 8 Newtons exerted on it what is it’s acceleration
a) 16 m/s^2
b) 4 m/s^2
c) 0.25 m/s^2
Answer:
b) 4m/s^2
Explanation:
F=ma
F=8N
m=2kg
a=?
a=F÷m
8/2=4
acceleration=4m/s²
How did plastics become the material of choice for so many varied applications?
Answer:
people as: it Is less expensive. easy to carry
______________ have properties of both metals and non metals.
Answer:
gold
Explanation:
what is the gram formula mass for Mg(OH)2
Answer:
58.33 g/mol
Explanation:
Which of the following best describes a possible carbon compound?
Answer:One carbon atom forms a double bond with an oxygen atom and two single bonds with two hydrogen atoms
Explanation:
Cunoscându-se că la 25C presiunea oxigenului dintr-un recipient este de 4 atmosfere, să se afle la ce temperatură oxigenul din recipient va avea presiunea de 8 atmosfere
Answer:
The container will have a pressure of 8 atm when the temperature is 50 degrees Celsius
Explanation:
To calculate this temperature, we need a gas law that relates temperature and pressure.
This is the Gay Lussac’s law and we know from it that temperature and pressure are directly related
Thus;
P1/T1 = P2/T2
From the question;
P1 = 4 atm
T1 = 25 degrees celsius
P2 = 8 atm
T2 = ?
Substituting these values, we have;
4/25 = 8/T2
4T2 = 8 * 25
4T2 = 200
T2 = 200/4
T2 = 50 degrees Celsius
How much is 1 mole of water molecules?
Answer:
Hey mate,
Here is your answer. Hope it helps you.
18 grams.
Explanation:
The mass of one mole of any atom/molecule is equal to its atomic molecular mass in grams.
The molecular formula of water is
H
2
O
The atomic mass of
H
= 1
The atomic mass of
O
= 16
In a sense, the formula means
H
+
H
+
O
So... 1 + 1 + 16 = 18
Therefore, the mass of one mole of water = 18 milliletres
49 grams of sulfuric acid, H2SO4, is dissolved in 1 liter of solution. Determine the molarity (M).
Answer: .5m
Explanation:
What does the kinetic theory state?
State two characteristics of matter demonstrated by: (a)-diffusion (b)-brownian motion
Answer:
Explanation:
a) This is to show that particles are in constant motion (and that matter is made of particles) with kinetic energy which enables particles of one matter to intermix with particles of another matter. this is known as diffusion. For example, the fragrance of a burning incense stick could be felt even at the farther end of the room because particles from the incense stick rise and intermix with the particles of air. T hey diffuse and spread all over the room.
b) Brownian motion is a constant zig-zag motion particles undergo. This can be noticed in a colloidal solution. particles of a colloidal solution remain active as they are charged with the same charge (all the particles of a certain solution carry the same charge). This causes each of them to repel from each other thus putting them into constant motion (kinetic energy). Thus, this too shows that particles are in constant motion (and that matter is made of particles).
10 moles of carbon dioxide has a mass of 440 g. What is the relative formula mass of carbon dioxide?
Answer: 44g
Explanation: The formular for finding Moles is ;
Moles = Mass / Molar Mass or Formular Mass.
Base on this question; Moles = 10, Mass = 440g, and Formular Mass = ?
Making 'Formular Mass', subject of the formular; we thus have;
Formular mass = Mass / Moles = 440/ 10 = 44g
why is it difficult to obtain oxygen from water
Answer:
Combined with Hydrogen
Explanation:
The following equation is an example of what type of reaction? " A+B --> AB - decomposition - catalyst - chain reaction - combination/ synthesis
Answer:
The equation is an example of combination/synthesis.
Explanation:
A + B → AB
The definition of synthesis is the act of simpler compounds being combined together to make a more complex compound. Both A and B are being combined to each other to make AB. So, the given equation shows a synthesis reaction.
Which characteristic gives the most information about what kind of element
an atom is?
A. The atomic number
B. The atomic mass
C. The number of electrons
D. The number of neutrons
Answer:
A. The atomic number
the anwer is B.The atomic mass because atoms may be similar atomic mass ,number of electron,proton,and neutron by the presence of isotope but no two atoms have the same atomic number
If 12.5 grams of strontium hydroxide is reacted with 150 mL of 3.5 M carbonic acid, identify the limiting reactant.
Answer:
Sr(OH)₂ will be the limiting reagent.
Explanation:
First of all, you should know the following balanced chemical equation:
2 H₂CO₃ + 2 Sr(OH)₂ → 4 H₂O + Sr₂(CO₃)₂
The balanced equation is based on the Law of Conservation of Mass, which says that matter cannot be created or destroyed. Therefore, the number of each type of atom on each side of a chemical equation must be the same.
The limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
To determine the limiting reagent, it is possible to use the reaction stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction). By stoichiometry the following amounts in moles react:
strontium hydroxide: 2 molescarbonic acid: 2 molesNow, you know the following masses of the elements:
Sr: 87.62 g/moleO: 16 g/moleH: 1 g/moleSo the molar mass of strontium hydroxide is:
Sr(OH)₂= 87.62 g/mole + 2*(16 g/mole + 1 g/mole)= 121.62 g/mole
You apply the following rule of three, if 121.62 grams of hydroxide are present in 1 mole, 12.5 grams in how many moles are they?
[tex]moles of strontium hydroxide=\frac{12.5 grams*1 mole}{121.62 grams}[/tex]
moles of hydroxide= 0.103 moles
On the other hand, you have 150 ml of 3.5 M carbonic acid. Since molarity is the concentration of a solution expressed in the number of moles dissolved per liter of solution, you can apply the following rule of three: if in 1 L there are 3.5 moles of carbonic acid, in 0.150 L (being 1 L = 1000 mL, 0.150 L = 150 mL) how many moles of acid are there?
[tex]molesofcarbonicacid=\frac{0.150 L*3.5 moles}{1 L}[/tex]
moles of carbonic acid= 0.525 moles
Finally, to calculate the limiting reagent, you can use a simple rule of three as follows: if by stoichiometry 2 mole of strontium hydroxide reacts with , how much moles of carbonic acid will be needed if 0.103 moles of strontium hydroxide react?
[tex]molesofcarbonicacid=\frac{0.103 moles of strontium hydroxide*2 moles of carbonic acid}{2 moles of strontium hydroxide}[/tex]
moles of carbonic acid= 0.103 moles
But 0.525 moles are available. Since more moles are available than you need to react with 0.103 moles of strontium hydroxide, Sr(OH)₂ will be the limiting reagent.
While hiking in Costa Rica, Bert discovers a new species of arthropod. Which characteristics should he look at to determine in which group it belongs?
Answer:
Characteristics outlined below
Explanation:
Anthropods, though they generally possess exoskeleton, segmented bodies and joint appendages, are divided into four (4) groups:
Tracheata (breath through channels in their bodies. E.g. insects)Chelicerata (More than four legs, one pir of chelicerae i.e. claw or pincer. E.g. Scorpions and spiders)Crustaceans (Have a large rigid exoskeletal, without a circulatory system. E.g. Shrimps, crabs)Trilobite (extinct three-headed/lobed marine species)10 grams of sodium hydroxide, NaOH, is dissolved in 0.25 liters of solution. Determine the molarity (M)
Answer:
1M
Explanation:
The molarity of a substance is defined as the number of moles of the substance divided by how many liters the solution is. NaOH has a molar mass of about 40 grams, meaning that 10 grams of it would be 0.25 moles. 0.25/0.25= a molarity of 1.
Hope this helps!
A solution of ammonia has a ph of 11.8. What is the concentration of OH- ions in the solution?
Answer: The concentration of [tex]OH^-[/tex] ions in the solution is 0.0063 M
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pOH is calculated by taking negative logarithm of hydroxide ion concentration.
[tex]pOH=-\log [OH^-][/tex]
[tex]pH+pOH=14[/tex]
[tex]11.8+pOH=14[/tex]
[tex]pOH=2.2[/tex]
Putting in the values:
[tex]2.2=-\log[OH^-][/tex]
[tex][OH^-]=[/tex] 0.0063 M
Thus the concentration of [tex]OH^-[/tex] ions in the solution is 0.0063 M
In a chemical reaction equation, which side of the arrow is the reactant?
" A+B --> AB"
- left
- right
- there are no reactants in equations.
Answer:
Left.
Explanation:
A+B --> AB
reactants product
Which of these does not describe the process the Wright brothers used to
create the first airplane?
A. The Wright brothers figured out how to outfit the plane with wings
that flapped, similar to birds' wings,
B. The Wright brothers used wind-tunnel tests to evaluate their
designs
C. The Wright brothers used the engineering process to come up
with its design.
D. The Wright brothers tested several model planes with similar
designs
Answer: A. The Wright brothers figured out how to outfit the plane with wings that flapped, similar to birds' wings,
Explanation: A p e x
Answer:
A
Explanation:
A p e x
PLS HELP NOW WILL GIVE BRAINLIEST
liquids have:
A. fixed size and shape
B. fixed size but not fixed shape
C. neither fixed size or shape
Answer:
Liquids, because they flow, can occupy whatever shape their container has, so they do not have a fixed shape. Because the particles in liquids are very close together (barely further apart than in solids) liquids do not easily compress, so their volume is fixed. hope that helps love!
help me with this question please
Answer:
Noble gases b/c its melts quicly that why enjoy
Balance the following reaction. P4 + 3 O2 → 2P2O5
Answer:
the answer to fill the blank is 5
Explanation:
i just did the lesson :)
Answer:
5
Explanation:
What is the perecentage yield of a reaction in which 200g PCl3 reacts with excess water to form 128g HCl according to the f.F reaction? PCl3 +3H2O=H3PO3+ 3HCl
Answer:
The percentage yield is 80.36% (see calculations in attachment).
Explanation:
The theoretical yield of the reaction is the amount of product that would result if all the limiting reagent reacted. The theoretical yield is calculated using the balanced equation.
In practice, the actual yield, or the amount of product actually obtained from a reaction, is almost always less than the theoretical yield.
To determine how efficient this reaction is, we need to calculate the percent yield, which describes the proportion of the actual yield to the theoretical yield. It is calculated as follows:
[tex] %yield = actual yield ÷ theoretical yield × 100% [/tex]
First we need to make sure that the equation is properly balanced. In the question they provide the balanced equation.
Since water is in excess, we calculate the theoretical yield using PCl₃.
Newton’s first law of motion states that an object at rest stays at rest,and an object in motion stays in motion,unless acted on by an unbalanced force.
Answer: yes that is true
Explanation:
newtons first law does state that.
Answer:
1. An overall net force must be applied to an object before it can move.
2. Newton’s first law of motion is also known as the law of inertia.
3. Newton’s first law applies to an object whether it is moving or not.
Explanation:
Edge
which indicator has to be used in order to get an emerald green color at a pH of 9?
a) universal indicator
b) methyl orange indicator
c) thymol blue indicator
d) cyanidin
Answer:
D) Cyanidin indicator
Explanation:
Cyanidin indicator has to be used in order to get an emerald green color at a pH of 9.
What is an indicator?Indicators are substances that change colour when they are added to acidic or alkaline solutions.
In nature, cyanidin is a reddish-purple (magenta) pigment. It is the major pigment in berries [4] and other red-coloured vegetables such as red sweet potato and purple corn. It appears as a blue-reddish or purple pigment in the plant.
Cyanidin indicator has to be used in order to get an emerald green colour at a pH of 9.
Learn more about indicators here:
https://brainly.com/question/488857
#SPJ2
