Answer:
40.5 g/mL
Explanation:
Density is a measure of a substance's mass over its volume.
d = m/v
Therefore d = 255.15g/6.3mL = 40.5 g/mL
precautions of a radioactive decay lab ?
Answer:
Don't touch radioactive waste with bare hands
Don't eat the radioactive thing
Wear protective eyewear
Wear lab coat/gloves
Explanation:
https://ehs.princeton.edu/laboratory-research/radiation-safety/radioactive-materials/handling-radioactive-materials-safely
Princeton article
Does a animal cell have cytolysis?
Answer:
The presence of a cell wall prevents the membrane from bursting,so cytolysis only occurs in animal and protozoa cells which do not have cell walls.
Explanation:
Describe the relationship between the potential difference across the resistor and
the current through the resistor.
Ohm's Law states that for a linear circuit the current flowing through it is proportional to the potential difference across it so the greater the potential difference across any two points the bigger will be the current flowing through it.
(I'm happy)
CaC2(s) + 2H2O(l) --> Ca(OH)2(aq) + C2H2(g) In the reaction above, 0.5487 grams of calcium carbide are completely consumed to produce acetylene gas, C2H2. What volume (in mL) will this gas occupy if it is collected at 43 degrees Celsius and 0.926 atm pressure
Answer:
239.7mL
Explanation:
Using the general gas equation;
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas constant (0.0821 Latm/molK)
T = temperature (K)
The balanced chemical equation in this question is as follows:
CaC2(s) + 2H2O(l) --> Ca(OH)2(aq) + C2H2(g)
From the equation, 1 mole of CaC2 produces 1 mole of ethylene gas, C2H2.
Using mole = mass/molar mass
Molar mass of CaC2 = 40 + 12(2)
= 40 + 24
= 64g/mol
mole = 0.5487/64
mole = 0.00857mol of CaC2
Hence, 0.00857mol of CaC2 produced 0.00857mol of C2H2
Based on the information provided, n = 0.00857mol, T = 43°C = 43 + 273 = 316K, p = 0.926 atm
PV = nRT
V = nRT/P
V = 0.00857 × 0.0821 × 316/0.926
V = 0.222/0.926
V = 0.2397L
In mL, volume = 0.2397 × 1000
= 239.7mL
What is needed to change a phase of matter?
The addition or subtraction of thermal energy. For example if you heat up an ice cube, it will melt to become water. If you heat it even more, it will evaporate.
How many grams of Ag2S
are produced from 10.0
grams of AgI?
10
AgI + Nazs
Ag2S +NaI
Answer:
10.0 g of AgI will produce 5.28 g of Ag₂S
Explanation:
The balanced equation of the reaction is given below:
2AgI + Na₂S ----> Ag₂S + 2NaI
From the equation of reaction, 2 moles of AgI produces 1 mole of Ag₂S
The moles of a substance is related to its mass by a quantity known as molar mass which is defined as the mass of one mole of that substance.
Molar mass of AgI = (108 + 127) g = 235 g
Molar mass of Ag₂S = (108 × 2 + 32) g= 248 g
Mass of 2 moles of AgI = 2 × 235 g = 470 g
470 g of AgI produces 248 g of Ag₂S
10 g of AgI will produce 248 /470 × 10 g of Ag₂S = 5.28 g
Therefore, mass of Ag₂S produced = 5.28 g
Circle all that apply for an anion.
a. Positively charged
b. Negatively charged
c. Metal
d. Nonmetal
e. Loses electrons when formed
f. Gains electrons when formed
g. Listed first in a compound
h. Listed second in a compound
Answer:
b. d. f. h
Explanation:
Anions are negatively charged. They are usually non metals with few exceptions. They need to gain electrons in order to form and they are always listed after cation in a compound.
1. How many liters of a 0.50 M solution are needed to give 3.5 moles of solute?
Answer:
The volume of solution in liters required to make a 0.250 M solution from 3.52 moles of solute is 14.08 liters of solution
Explanation:
The question relates to the definition of the concentration of a solution which is the number of moles per liter (1 liter = 1 dm³) of solution
Therefore we have;
The concentration of the intended solution = 0.250 M
Therefore, the number of moles per liter of the required resolution = 0.250 moles
Therefore, the concentration of the required solution = 0.250 moles/liter
The volume in liters of the required solution that will have 3.52 moles of the solute is given as follows;
The required volume of solution = The number of moles of the solute/(The concentration of the solution)
∴ The required volume of solution = 3.52 moles/(0.250 moles/liter) = 14.08 liters
The required volume of solution to make a 0.250 M solution from 3.52 moles of solute = 14.08 liters.
Therefore the number of liters required to make a 0.250 M solution from 3.52 moles of solute = 14.08 liters.
Using standard formation enthalpies, calculate the standard reaction enthalpy for this reaction. 6CO2(g) + 6H2O(l)C6H12O6 + 6O2(g) ANSWER: kJ/mol
Answer:
2802.5 KJ/mol
Explanation:
Calculate standard enthalpy of the Reaction :
6CO2(g) + 6H2O(l)C6H12O6 + 6O2(g)
using standard formation enthalpies . hence the standard enthalpy of the reaction = 2802.5 KJ/mol
attached below is the detailed solution
5g of NaOH was dissolved in 1000cm3. 25cm3 of this solution neutralized 28.3cm3 of solution containing 7.2gdm-3 of impure H2SO4. Calculate I. The molarity of H2SO4 II. The concentration of the pure acid on gdm-3 III. % impurity of the acid
Explanation:
The balanced equation for the reaction between NaOH and H2SO4 is given as;
2NaOH + H2SO4 → Na2SO4 + 2H2O
2 mol of NaOH reacts with 1 mol of H2SO4
5g of NaOH was dissolved in 1000cm3.
Mass = 5 g
Molar mass = 40 g/mol
Volume = 1000 cm3 = 1 L
Number of moles = Mass / Molar mass
Number of moles = 5 / 40 = 0.125 mol
Molarity = Number of moles / Volume
Molarity = 0.125 / 1 = 0.125 M
25cm3 of this solution neutralized 28.3cm3 of solution containing 7.2gdm-3 of impure H2SO4.
CaVa / CbVb = Na / Nb ; where a = acid and b = base
Va = 28.3cm3
Vb = 25cm3
Ca = ?
Cb = 0.125 M
Na = 1
Nb = 2
I. The molarity of H2SO4
Solving for Ca;
Ca = CbVb * Na / (Va * Nb)
Cb = (0.125 * 25 * 1 ) / ( 28.3 * 2)
Cb = 0.0552 M
II. The concentration of the pure acid on gdm-3
Molarity = Mass conc / Molar mass
Mass Conc = Molarity * Molar mass
Mass Conc = 0.0552 * 98.079
Mass Conc = 5.41 g/dm3
III. % impurity of the acid
Percentage Impurity = Mass of pure / Mass of Impure * 100
Percentage Impurity = 5..41 / 7.2 * 100
Percentage Impurity = 75.14%
PLEASE HELP ME ASAP!!!!!! YOU GET 10 POINTS!!!!!!
For reaction below, describe how its equilibrium could be shifted in the indicated direction.
1. H2(g)+C12(g)<---------->2HC1(g)+thermal energy: shift to the left
2.C(s) +O2(g)<---------->CO2+thermal energy: shift to the right
Answer:
Here is the ANSWER KEY, it may also has other of the questions you don't know :)
Explanation:
https://sciencewithhorne.weebly.com/uploads/5/7/3/5/57358947/unit_11_hw_key.pdf
Q4
Which of the following is an example of nonpoint source pollution?
A. industrial effluent
B. Agricultural runoff
C. illegal dumping of waste
D. Oil leaking from your car
Answer:
Option C.
Ilegal dumping of waste
Explanation:
This is because non point source of pollution refers to source of pollution that are many and not directly one which is illegal or does not meet the legal term. This type of pollution does not have a point source, it has many sources and this type of pollution is cause by rainfall or precipitation. Where when the rain fall, it wash away the waste through to water bodies, causing pollution and endangering water bodies.
8. If a chemical reaction such as photosynthesis begins with 6 atoms of carbon (C), how many atoms of carbon (C) should be in the products? A. 12 atoms of carbon (C) B. 6 atoms of carbon (C) c. 3 atoms of carbon (C) D. 2 atoms of carbon (C)
A. 12 atoms of carbon (C)
B. 6 atoms of carbon (C)
C. 3 atoms of carbon (C)
D. 2 atoms of carbon (C)
Answer
b
Explanation:
Which series reveals the source of energy for coal?
coal chemicals sun
coal plants chemicals
coal animals sun
coal plants sun
Answer:
coal chemicals sun
Explanation:
an element has atomic number of 17 state the elements group and period number
Answer:
The element is in group 7, the halogens. The element is in the third period or row of the table.
Explanation:
Chlorine is element number 17.
do i have to know the chemical and physical properties of alloys? only chemistry students answer this.
Answer:
yes you do so you know how strong it is how maluble it's is so it can be customised to it's specific use
Answer:
alloy's properties are usually different from those of its component elements. Alloy constituents are usually measured by mass. Unlike pure metals, most alloys do not have a single melting point; rather, they have a melting range in which the substance is a mixture of solid and liquid.
physical properties of alloys:-Alloy steels have a wide range of special properties, such as hardness, toughness, corrosion resistance, magnetizability, and ductility. Nonferrous alloys, mainly copper–nickel, bronze, and aluminum alloys, are much used in coinage.
chemical properties of alloys:-Pure metals are useful but their applications are often limited to each individual metal's properties. Alloys allow metal mixtures that have increased resistance to oxidation, increased strength, conductivity, and melting point; Essentially any property can be manipulated by adjusting alloy concentrations.
dnt learn all thr properties.
these are the main properties..u can learn thse only. hope it will help u
True or False. Chemical changes only rearrange the elements that are
already present.
True or False. The reactants and the products of a chemical equation
always have the same number of atoms.
Here's link to the answer:
tinyurl.com/wpazsebu
Which of the nine substances are made of four elements?
Answer:
Oxygen mucury carbon dioxide and platinum
Explanation:
What is the mass of water released by the heating? Show your work or explain your reasoning.
Answer:
Dividing the mass of the water lost by the original mass of hydrate used is equal to the fraction of water in the compound. Multiplying this fraction by 100 gives the percent water in the hydrate.
Explanation:
The amount of water throughout the compound has been determined by dividing the mass of water wasted mostly by original quantity of hydrate used. The above fraction can be multiplied by 100 to get the hydrate's water content in percentages.
What is mass ?The proportion of matter that makes up an object is quantified by its mass. The kilogram, or kg, would be the fundamental SI unit of mass.
What is hydrate?Any substance that contains water through the form of H2O molecules is referred to as a hydrate. This water content by weight can vary, but it is typically fixed. The most well-known hydrates seem to be crystalline solids which decompose once the attached water is removed.
Therefore , The amount of water throughout the compound has been determined by dividing the mass of water wasted mostly by original quantity of hydrate used. The above fraction can be multiplied by 100 to get the hydrate's water content in percentages.
To know more about mass and hydrate.
https://brainly.com/question/11202174
#SPJ3
classify the following elements under metals, non metals and metalloids, boron, zinc Mercury, silicon, oxygen, nitrogen, sodium
Answer:
Zinc mercury transition metal
Silicon boron metalloid
Oxygen nitrogen non metal
Sodium alkali metal
Explanation:
Using the diagram, which two planes would intersect in HG?
Answer please .. :)
Answer:
I think D
Explanation:
it has both H and G in the planes.
help meeeeeeeeeeeeee
Answer:
XCl₂ + 2AgNO₃ —> X(NO₃)₂ + 2AgCl
The coefficients are: 1, 2, 1, 2
Explanation:
XCl₂ + AgNO₃ —> X(NO₃)₂ + AgCl
The equation can be balance as follow:
XCl₂ + AgNO₃ —> X(NO₃)₂ + AgCl
There are 2 atoms of Cl on the left side and 1 atom on the right side. It can be balance by writing 2 before AgCl as shown below:
XCl₂ + AgNO₃ —> X(NO₃)₂ + 2AgCl
There are 2 atoms of Ag on the right side and 1 atom on the left side. It can be balance by writing 2 before AgNO₃ as shown below:
XCl₂ + 2AgNO₃ —> X(NO₃)₂ + 2AgCl
Now, the equation is balanced.
The coefficients are: 1, 2, 1, 2
how is salt obtained or manufactrured
Answer:
There are three methods used to produce salt: solar, evaporation and rock mining.
Explanation:
2KCIO3 -> 2KCI+ 302
How many moles of oxygen are produced by
the decomposition of 6.0 moles of potassium
chlorate, KCIO3?
Answer:
9 moles
Explanation:
The balanced chemical equation for this decomposition reaction is as follows:
2KCIO3 → 2KCI+ 302
Based on this equation, 2 moles of potassium chlorate (KCIO3) decomposes to form 3 moles of oxygen gas (O2).
Hence, 6 moles of pottasium chlorate will decompose to produce;
6 × 3 ÷ 2
= 18 ÷ 2
= 9 moles of O2.
De la reacción 3Zn+ 2H2PO4----> Zn3(PO4)2 +2H2 por cada 9 moles de zinc cuantos moles de fosfato de zinc se producen
Answer:
Por cada 9 moles de zinc, 9 moles de fosfato de zinc se producen.
Explanation:
La reacción balanceada es:
3 Zn+ 2 H₂PO₄ → Zn₃(PO₄)₂ + 2 H₂
Por estequiometria de la reacción (es decir, la relación entre la cantidad de reactivos y productos en una reacción química), las siguientes cantidades de moles de cada compuesto participan de la reacción:
Zn: 3 moles H₂PO₄: 2 moleZn₃(PO₄)₂:1 mole H₂: 2 molesEntonces podes aplicar la siguiente regla de tres: si por estequiometria 3 moles de zinc produce 1 mol de fosfato de zinc, 9 moles de zinc cuántos moles de fosfato de zinc producirá?
[tex]moles de fosfato de zinc=\frac{9 moles de zinc*1 mole de fosfato de zinc}{3 moles de zinc}[/tex]
moles de fosfato de zinc= 9
Por cada 9 moles de zinc, 9 moles de fosfato de zinc se producen.
1. 2.00 L of gas is at 740 mm Hg. What is its volume at standard
pressure?
0.16
Explanation:
when you divided 1.2.00 with 740 you get this number.
1. A wave has a frequency of 800 Hz and a wavelength of 2000 cm. What speed
is this wave traveling?
Answer:
V=f*(wavelength)
V= (800)(20m)
16000m/s
Explanation:
Many ski resorts and mountain cities can be reached directly by planes which deposit travelers a mile or more above sea level. This can result in altitude sickness due to hypoxemia, or reduced oxygen in the blood, caused by the unaccustomed exposure to the lower atmospheric pressure at high elevations. On a given day, the prevailing atmospheric pressure in Albuquerque, NM (elevation 1620 meters) might be 0.799 atm. Calculate this pressure expressed in mmHg and in torr. Relationship between altitude and barometric pressure.
Answer:
See explanation
Explanation:
To convert from atm to mmHg
1 atm = 760 mmHg
0.799 atm = 0.799 atm * 760 mmHg/1 atm = 607.24 mmHg
To convert from atm to torr
1 atm = 760 torr
0.799 atm = 0.799 atm * 760 torr/1 atm = 607.24 torr
MgSO4 x 7H2O:
How
many molecules of
water are present
per magnesium
sulphate formulation
unit
Answer:In regards to writing the formula, we know that magnesium has a charge of 1+ and sulfate, SO4, has a charge of 1-. Sulfate is a polyatomic ion so the charge of the whole thing is (SO4)1-. When you combine them you end up with MgSO4 and the "heptahydrate" is seven water molecules.
Explanation:
Answer:
Iduno sorry po hsjsnaka
a wave transfers from one place to another
Answer:
mhm
Explanation:
