A student wants to conduct an investigation on vapor pressure Which statement describes how vapor pressure is related to an observable phase change?

A liquid boils when the vapor pressure equals the boiling point.
A liquid freezes when the vapor pressure equals the melting point.
A liquid freezes when the vapor pressure equals the atmospheric pressure.
A liquid boils when the vapor pressure equals the atmospheric pressure.

The Whole Electrical Bonding Investigation Plan Quick check

1) B. boiling point, surface tension, vapor pressure

2) A. glycerin

3) C. the temperature at which additional heat energy causes the substance to change from a liquid to a gas

4) D. Heat each substance in liquid form to its boiling point. Measure the temperature of each substance

5) A. A liquid boils when the vapor pressure equals the atmospheric pressure.

(what is the meaning of aids?) (what is the meaning of cushions?) (name 5 citrus fruits) ( what are antibodies?) (what are hormones?)​

A model for a potential chemical reaction is shown here. Evaluate the model and the reaction shown. Which statements are correct about this model. Select ALL that apply.

A) The law of conservation of matter is followed in this model.

B) Conversation of matter is not observed because of some of the atoms are converted into energy in the reaction.

C) Conservation of matter is observed because there are the same number of each atom on both sides of the reaction.

D) Conservation of matter is not observed because there are different numbers of molecules in the reactants and the products. ​

This element has an atomic number lower than aluminum and is in group 14

Complete the sentence. When a base is added to water, hydrogen ions __________.

In an ionic compound, the total positive charge of all the positive ions ____ the total negative charge of all the negative ions.

Question 1 (2 points)
Which option can be classified as a pure substance?

Question 1 options:

heterogenous mixture


solution


homogenous mixture


compound

Question 2 (2 points)
Law of conservation of mass states that:

Question 2 options:

matter is destroyed


matter does not change


matter is neither created nor destroyed


matter is created

Question 3 (2 points)
What is a property of bases?

Question 3 options:

all of the above


Sour taste


Slippery touch


Ability to form hydronium ions+

Question 4 (2 points)
Which property do solutions with low pH values have?


What does it mean to have a neutral pH? - Aseptic Health

Question 4 options:

have a -OH group


feels slippery


turns litmus paper blue


tastes sour

Question 5 (2 points)
How do the products of chemical reactions compare to their reactants?

Question 5 options:

The products often have completely different properties than the reactants.


The products are usually more toxic than the reactants.


The products usuallyhave more mass than the reactants.


The products usually have more atoms than the reactants.

Question 6 (2 points)
Which of the following is an example of a physical change?

Question 6 options:

Water freezing into ice.


A piece of wood burning.


A toy car rusting.


Zinc producing hydrogen gas when mixed with water.

Question 7 (2 points)
What might happen if you mixed a strong acid with an equally strong base?

Question 7 options:

You would see an explosive chemical reaction.


The base would destroy the acid.


You'd wind up with a pH-neutral salt and water.


The acid would destroy the base.

Question 8 (2 points)
In the equation shown, what are the reactants?

2H2+O2àH2O

Question 8 options:

Hydrogen and oxygen molecules (2H2 and O2 )


Ice crystals


Hydrogen atoms (H)


Water molecules (H2O)

Question 9 (2 points)
Which phrase most accurately describes a chemical change?

Question 9 options:

A change in form


A change in taste


A change on the molecular level


A change in appearance

Question 10 (2 points)
What does it mean when there is a physical change?

Question 10 options:

A new substance has been formed.


Matter has changed from one substance into a new substance.


Matter has changed size, shape or form


Matter has changed on the molecular level.

help pls ill give 20 points!

Which objects are scratched?

a stone is projected horizontally with 20 metre per second from the top of a tall building calculate its position in velocity after 3 seconds neglecting the air resistance .​

PLEASE HELP ASAP 30 POINTS!!!!




Voltage ______
Question 1 options:


causes current


pushes free electrons around a circuit


is measured in Volts


all of the choices

a substance that can be broken down into simpler substances

A solid magnesium flare has a mass of 1300 g and a volume of 743 cm3. What is the density of the magnesium?

Some single-celled organisms make copies of themselves through mitosis. Which describes the function of the cell cycle in such single-celled organisms?

During ionization, metals lose electron, this change is called?​

which ionization process requires the most energy?

C. A - ion (negative ion, one with extra negative charge)?

Which solution has the greatest number of hydrogen ions? blood, pH = 7. 2 lemon juice, pH = 2 soda, pH = 3. 5 bleach, pH = 13. 5.

What element is being reduced in the following redox reaction? Cr(OH)4-(aq) ClO-(aq) → CrO42-(aq) Cl-(aq).

How does the microscopic arrangement of particles affect the microscopic behavior of the solution?

can someone plaexplain to me what is 'first ionisation energy' in simple words coz my small brain can't understand it​

5.The amount of pollution produced by cars was measured for cars using gasoline containing different amounts of lead. what is the independent, dependent and controlled variables?

can someone send the working and answer for this question with formulas used and all

2KClO3 —> 2KCl + 302 this equation represents both a ___ reaction AND a(n) ___ reaction.

A. combustion; decomposition
B. single replacement; combustion
C. combustion; oxidation-reduction
D. decomposition; oxidation-reduction

Four substances at the same temperature absorb equal

amounts of energy. The specific heat of the four

substances are listed below.

Substance

A. 1.45 J/g °C

B. 2.32 J/g °C

C. 0.98 J/g °C

D. 1.95 J/g °C

Which substance would show the GREATEST increase in

temperature?

A

B

C

D

What is the
name of the
compound
Na2Co3?

Help please!!!!!!!!!!!!!!!!!!!!…

Question 5 (5 points)
Use the picture below to determine if the following statements are observations or if the statements are inferences. Place a “O” in the blank for an observation and “I” for an inference.


BLANK 1: A person is in the water
BLANK 2: The weather is cold
BLANK 3: The tree branch is broken
BLANK 4: If the boy crawled out of the water the goat would push him back in
BLANK 5: The boy fell off the branch

Having studied the data for patterns and trends, you should now be able to draw
some conclusions about how knowing the half-life of the element Lokium would
help you determine the absolute age of rock in which this element is found. In a
paragraph, create an imaginary example of finding a given amount of Lokium and
DOL in a rock, and then determining the absolute age of that rock. Assume that
each trial represents 1,000 years

Please help I will Mark Branlist
please justify and explain aswell

If an object absorbs all the light that hits it, the object appears to be

What is the percentage of Aluminum in Aluminum Sulfate?