Answer:
Zinc is an element.
Explanation:
Compounds are composed of two or more elements
Answer:
element
Explanation:
zinc is an element with atomic number 30
74g of Ca(OH)2 (74 g/mol) in 340 ml solution
Answer:
This question is asking to calculate the molarity of the solution based on the information provided.
The answer is 2.94M
Explanation:
Molarity of Ca(OH)2 solution = number of moles (n) ÷ volume (V)
Using the formula below to calculate number of moles of Ca(OH)2.
mole = mass/molar mass
Molar mass of Ca(OH)2 = 74 g/mol
mole = 74g/74g/mol
mole = 1mol
Volume of Ca(OH)2 solution = 340ml = 340/1000 = 0.340 L
Molarity = 1/0.340
Molarity = 2.94M
What happens during a lunar eclipse?
A
Earth passes between the sun and the moon.
B
The moon passes between the sun and Earth.
C
The sun passes between Earth and the moon.
D
Earth, the sun, and the moon are at right angles in space.
Answer:
A.EARTH PASSES BETWEEN THE SUN AND THE MOONExplanation:
When Earth passes directly between Sun and Moon, its shadow creates a lunar eclipse.
pabrainliest po plss:)
Which part of an organism is LEAST likely to form a fossil?
A. skin
B. tooth
C. bone
D. shell
Answer:
[tex]\huge \fbox \pink {A}\huge \fbox \green {n}\huge \fbox \blue {s}\huge \fbox \red {w}\huge \fbox \purple {e}\huge \fbox \orange {r}[/tex]
A. Skin
Explanation:
Skin unlike teeth, bones & shells is fragile & get decomposed easily under the soil.
Answer:
um a I think because when you look at dinosaur you don't see their skin anymore just like the bones and teeth
An endothermic dissolution process a. absorbs energy as heat and has positive enthalpy of solution. b. releases energy as heat and has positive enthalpy of solution. c. absorbs energy as heat and has negative enthalpy of solution. d. releases energy as heat and has negative enthalpy of solution.An endothermic dissolution process a. absorbs energy as heat and has positive enthalpy of solution. b. releases energy as heat and has positive enthalpy of solution. c. absorbs energy as heat and has negative enthalpy of solution. d. releases energy as heat and has negative enthalpy of solution.
Answer:
a. absorbs energy as heat and has positive enthalpy of solution.
Explanation:
A reaction can either be exothermic or endothermic. An endothermic reaction, as the dissolution described in the question, is that which absorbs heat energy from the surroundings in order to start the reaction.
Because an endothermic reaction makes heat lost from the surroundings, the enthalpy (∆H) of the solution will be positive (+). ∆H is got by finding the difference between the enthalpy of the reactants and products and since the enthalpy of a product in endothermic reaction is more, the enthalpy change (∆T) will be positive.
The greenhouse gas released into the atmosphere as a result of livestock digesting their food is called carbon dioxide
True
False
Answer:
False
Explanation:
Cows and other livestock release methane, which is a gas like Carbon Dioxide, but not the same thing, even though it does contribute into Carbon Dioxide.
4. How would you calculate the poH of a base when given the
concentration of [OH]-?
Answer:
Use pOH = -log₁₀ [OH-]
Explanation:
pOH can be calculated from the concentration of hydroxide ions using the formular below:
pOH = -log₁₀ [OH-]
The pOH is the negative logarithm of the hydroxide ion concentration.
H2O2 (yield) H2O + O2
If 650 grams of hydrogen peroxide is allowed to decompose, how much water and
oxygen will be created? If 255 grams of oxygen are collected, what is the percent
yield?
How many grams would be in 1.752 x10^26 formula units of Ca(No3)2
Answer:
47730 grams.
Explanation:
First we convert 1.752x10²⁶ formula units of Ca(NO₃)₂ into moles, using Avogadro's number:
1.752x10²⁶ formula units ÷ 6.023x10²³ formula units/mol = 290.88 molThen we convert 290.88 moles of Ca(NO₃)₂ into grams, using the molar mass of Ca(NO₃)₂:
290.88 mol * 164.088 g/mol = 47730 gA sexually mature seahorse can produce thousands of offspring. What is the BEST reason overproduction of offspring by marine organisms is considered to be a reproductive advantage?
A:It increases competition.
B: It decreases competition.
C: It contributes to the organism’s biological success.
D: It causes stress on the environment which will apply stress to the creature to adapt.
13) Which "conversion tool" below would you use to complete this
conversion?
Consider an ideal gas contained in a cylinder with the volume 34.4L, temperature 667K and pressure 2atm.What will be pressure of the gas if it is heated at 1000k and the volume becomes 50L.
Given :
An ideal gas contained in a cylinder with the volume 34.4L, temperature 667K and pressure 2 atm.
To Find :
What will be pressure of the gas if it is heated at 1000k and the volume becomes 50L.
Solution :
We know, by ideal gas equation :
[tex]Pv = nRT[/tex]
Now, in the given question only their are two state and also their is no leakage so amount of gas is also constant.
So,
[tex]\dfrac{P_1V_1}{T_1} = \dfrac{P_2V_2}{T_2}\\\\\dfrac{2\times 34.4}{667} = \dfrac{P_2 \times 50}{1000}\\\\P_2 = \dfrac{2\times 34.4 \times 1000}{667 \times 50}\ atm\\\\P_2 = 2.06 \ atm[/tex]
Therefore, the pressure of gas is 2.06 atm.
Both Arrhenius and Bronsted-Lowry defintions of an acid are similar. According to both of these definitions, an acid is a compound that -
donates a pair of electrons
contains a nonmetal anion
donates a hydrogen ion
should be labeled as corrosive
Answer:Donates a hydrogen ion
Explanation:
How many grams of H2 are needed to completely react within 50g of N2?
Answer: 10.7 grams
Therefore, 10.7 grams of Hydrogen are necessary to fully react with 50.0 grams of Nitrogen.
A rocket launches because of __________.
A. an opposite reaction
B. it's large mass
C. its gravity
D. air resistance
Answer:
an opposite reaction
Earth's gravity is still pulling down on the rocket. When a rocket burns propellants and pushes out exhaust, that creates an upward force called thrust. To launch, the rocket needs enough propellants so that the thrust pushing the rocket up is greater than the force of gravity pulling the rocket down.
0.630 moles of sodium chloride are how many grams (with calculation)
Answer:
Heyaa!! Im Pinky and Im here to inform you that your answer is...
Explanation:
!!! 36.8189451 Grams !!!
Have an amazing day!!!
~Pinky~!!
The valences of metal x,y and z are 1,2 and 3 respectively. What are the formulae of their;a) hydroxides, b) sulphates, c) hydrogen, d) carbonates, e) nitrates, f) phosphates
Answer:
See answer below
Explanation:
AS we know that the valence for those metals X, Y, and Z are 1, 2 and 3, we can determine the formula of each compound.
1. Hydroxides.
An hydroxide is formed when an oxyde of a metal reacts with water. When this happens, the general molecular formula is:
Meₐ(OH)ₙ
Where:
a: valence or charge of the hydroxide (Which is -1)
n: valence of the metal.
Following this, the formula for X, Y and Z would be:
XOH
Y(OH)₂
Z(OH)₃
2. Sulphates
Sulphates follow a similar rule of hydroxide in the general molecular formula, but instead of having a charge of -1, it has a charge of -2 so:
Mₐ(SO₄)ₙ
So, following the rule:
X₂SO₄
Y₂(SO₄)₂ ------> YSO₄
Z₂(SO₄)₃
3. Hydrogens
Following the same rule as the previous, hydrogens works with a charge of -1, so:
MₐHₙ
Then:
XH
YH₂
ZH₃
4. Carbonates.
This follows the same rule as sulphates, with the same charge so:
Mₐ(CO₃)ₙ
Then:
X₂CO₃
YCO₃
Z₂(CO₃)₃
5. Nitrates
Follow the same rule as the hydroxides, with the same charge of -1.
Mₐ(NO₃)ₙ
Then:
XNO₃
Y(NO₃)₂
Z(NO₃)₂
6. Phosphates
In the case of phosphates, these have a charge of -3 so:
Mₐ(PO₄)ₙ
Then:
X₃PO₄
Y₃(PO₄)₂
Z₃(PO₄)₃ ----> ZPO₄
Hope this helps
Many people try to eliminate fat from their diets. Which is one reason it is
necessary for humans to eat fat?
Answer:
C
Explanation:
While it is common to notice that many people avoid food that contain fat due to the fact that they are avoiding the adverse implications of fat consumption, the consumption of fat also has some advantages.
Prominent among the advantages of fat in the body is that fat cushions the internal organs. This cushioning of the internal organs avoids sudden damage to these organs.
For this reason, it is necessary for humans to eat fat.
36 g of KOH was dissolved in 800 mL of water. What is the
molality of the solution? (Molar mass of KOH = 56 g/mol,
density of water = 1.00 g/mL) ___ m.
Answer: 0.8 m
Explanation:
Which of the following are HETEROGENEOUS mixtures from this list (check all that apply).
A. Air
B. Sweet Tea
C. Trail mix
D. Soil
E. Beach sand
F. Water
At a high concentration do you have more or less particles per unit volume
Answer:
More particles per unit volume
Explanation:
Concentration means the amount of solute in a solution. Now, the amount of solute also means the number of particles of solute present in a solution.
Hence, when we use the term "high concentration", we imply that the amount of solute present or the number of particles present in a solution is high.
Thus, at high concentration, there are more solute particles than solvent particles in a solution.
a concentrated solution of sulfuric acid, H2SO4, has a concentration of 18.0 M. How many mL of the concentrated acid would be required to make 250. mL of a 1.00 MH2SO4 solution?
Answer: A 13.88 mL of the concentrated acid would be required to make 250. mL of a 1.00 M [tex]H_{2}SO_{4}[/tex] solution.
Explanation:
Given: [tex]M_{1}[/tex] = 18.0 M, [tex]V_{1}[/tex] = ?
[tex]M_{2}[/tex] = 1.00 M, [tex]V_{2}[/tex] = 250 mL
Formula used to calculate the volume of concentrated acid is as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]
Substitute the values into above formula as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}\\18.0 M \times V_{1} = 1.00 M \times 250 mL\\V_{1} = \frac{1.00 M \times 250 mL}{18.0 M}\\= 13.88 mL[/tex]
Thus, we can conclude that 13.88 mL of the concentrated acid would be required to make 250. mL of a 1.00 M [tex]H_{2}SO_{4}[/tex] solution.
The balanced chemical equation for the reaction between sodium chloride and silver nitrate is:
NaCl ( aq ) + AgNO3 ( aq ) AgCl ( s ) + NaNO3 ( aq )
We can interpret this to mean:
1 mole of sodium chloride and mole(s) of silver nitrate
React to produce:
mole(s) of silver chloride and mole(s) of sodium nitrate
Answer:
We can Interprete it as 1mole of Sodium Chloride and 1mole of Silver Nitrate React to Produce
1Mole of Silver Chloride and 1Mole of Sodium Nitrate
Answer:NaCL
Explanation:Edg
Determine the empirical formula of a compound containing 0.57% hydrogen, 72,1% Todine, and 27.3\% oxygen.
what uses a coil that is a temporary electromagnet
Answer: transformers, generators ,inductors, electric motors
Explanation:
A small ferret comes to help Roxie with the rock that is blocking her den. They push with a total force of 90 N moving the boulder a distance of 5m. How much work do they do?
Answer:
Work = 450 J
Explanation:
Force = 90N
Distance = 5m
Work = ?
The relationship between these quantities is given by the equation:
Work = Force * Distance
Work = 90 * 5
Work = 450 J
Use the dichotomous key to identify these plant leaves.
Leaves from which plant are shown?
pine
catalpa
dogwood
maple
Answer:
catalpa
Explanation:
i took the test
What structure behind the eardrum touch that membrane?
Answer:
The middle ear is the portion of the ear internal to the eardrum, and external to the oval window of the inner ear. The mammalian middle ear contains three ossicles, which transfer the vibrations of the eardrum into waves in the fluid and membranes of the inner ear.
Explanation:
What is the pH of a 0.21 M solution of LiOH?
Answer:
13.32
Explanation:
pOH=-log(0.21)=0.68
pH=14-pOH=14-0.68=13.32
Which is the balanced equation for a reaction between hydrogen gas and oxygen gas
Answer:
it is known that two molecules of hydrogen gas, H2, react with one molecule of oxygen gas, O2, to form two molecules of water, H2O. This reaction may be represented by the chemical equation 2H2+O2→2H2O. The formula weight of hydrogen gas is 2.01594, that of oxygen gas 31.9998, and that of water 18.01534
Answer:
it is known that two molecules of hydrogen gas, H2, react with one molecule of oxygen gas, O2, to form two molecules of water, H2O. This reaction may be represented by the chemical equation 2H2+O2→2H2O. The formula weight of hydrogen gas is 2.01594, that of oxygen gas 31.9998, and that of water 18.01534
Explanation:
the user above
Its is the change in energyof a neutral atom when an electron to the atom to form negativeion, thus neutral atom gain electon.What property of element is being described
Answer:
Electron affinity.
Explanation:
An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such determines or defines the structure of a chemical element.
Generally, atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.
Electron affinity can be defined as the ability of an atom of a chemical element to accept or accommodate an electron.
This ultimately implies that, electron affinity is the change in energy of a neutral atom of a chemical element when an electron is added to the atom to form negative ion, thus, a neutral atom gain electron.
In Chemistry, electrons can be defined as subatomic particles that are negatively charged and as such has a magnitude of -1.