All categories

3 years ago

Which of the following processes are physical changes?

Chemistry

2 answers:

lubasha [3.4K]3 years ago

8 0

C) cutting a snowflake out paper
because someone has to physically cut the paper into a snowflake

Stolb23 [73]3 years ago

7 0

C) and d) are physical changes while b) is chemical

You might be interested in

H2PO4-(aq) ⇆ H+(aq) + HPO42-( which ion plays the role of hydrogen ion donor and which one plays the hydrogen ion acceptor in BP

alexgriva [62]

Answer:

<u>H2PO4- is a proton donor and HPO42_ is a proton acceptor</u>

Explanation:

Step 1: What are hydrogen ion donor and acceptor

in the following reaction we see that:

⇒ H2PO4- is more likely to give a H+ ion to form HPO42-.

⇒HPO42- is more likely to take a H+ ion, to form H2PO4-

The reaction of an acid in water solvent is described as a dissociation :

HA ⇔ H+ + A-

⇒where HA is a proton acid

So, H2PO4- = HA and HPO42- = A-

Acids are proton donors. So, <u>H2PO4- is a proton donor and HPO42_ is a proton acceptor</u>

6 0

3 years ago

PLEASE SOMEONE! The density of the acetic acid solution is 1.05 g/mL. Calculate the %(m/m) of the acetic acid solution (convert

tigry1 [53]

Answer:

The Percentage concentration of acetic acid = 1.39 %

Explanation:

Density of acetic acid solution = 1.05 g/mL

Volume of acetic acid solution = 0.1 L = 100 mL

From the formula, Density = mass / volume; mass = density × volume

Mass of acetic acid solution = 1.05 g/mL × 100 mL = 105 g

Molar concentration of acetic acid solution = 0.243 mol/L

Molar mass of acetic acid, CH₃COOH = (12 × 2 + 1 ×4 + 16 ×2) = 60 g/mol

From the formula, mass concentration = molar concentration × molar mass

Mass concentration of acetic acid, CH₃COOH = 0.243 mol/L × 60 g/mol = 14.58 g/L

In one liter of acetic acid solution, there are 14.58 g of acetic acid. Therefore, in 0.1 L, there will be 14.58 × 0.1 = 1.458 g of acetic acid.

Percentage concentration of acetic acid = mass of acetic acid / mass of acetic acid solution × 100%

Percentage concentration of acetic acid = (1.458 / 105) × 100% = 1.39 %

The Percentage concentration of acetic acid = 1.39 %

8 0

3 years ago

What do helium (He), neon (Ne), and argon (Ar) have in common?

IrinaK [193]

Answer:

The answer is: D

Explanation:

A. They have the same number of electron energy shells. Is false, all the elements are in different periods so, they have different number of lectron energy shells.

B. They are all Halogens. No, is wrong, halogens are F, Cl ,Br

C. They have the same number of electrons. is wrong, if they had the same number of electrons they must be they same element and they aren't the same.

D. They are all Noble gases. Yes, it's true they are noble gases, they are the first group in the periodic table from the right.

6 0

3 years ago

Read 2 more answers

What mass of boron sulfide must be processed with 2.1 x 10 4g of carbon to yield 3.11 x 10 4 g of boron and 1.47 x 10 5 g of car

Basile [38]

The reaction between boron sulfide and carbon is given as:

2B2S3 + 3C → 4B + 3CS2

As per the law of conservation of mass, for any chemical reaction the total mass of reactants must be equal to the total mass of the products.

Given data:

Mass of C = 2.1 * 10^ 4 g

Mass of B = 3.11*10^4 g

Mass of CS2 = 1.47*10^5

Mass of B2S3 = ?

Now based on the law of conservation of mass:

Mass of B2S3 + mass C = mass of B + mass of CS2

Mass of B2S3 + 2.1 * 10^ 4 = 3.11*10^4 + 1.47*10^5

Mass of B2S3 = 15.7 * 10^4 g

4 0

3 years ago

1-magma wich flows through channles to the surface will produce a???

AlladinOne [14]

Answer:

thats one hint. but for 1 it will produce lava

Explanation:

number 2

some of the Earth's grandest mountains are composite volcanoes--sometimes called stratovolcanoes. They are typically steep-sided, symmetrical cones of large dimension built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs and may rise as much as 8,000 feet above their bases

6 0

3 years ago