Which element do plants need a lot of in order to go?

What is the ph of a peach with a [ –oh] = 3.2 × 10 –11 m?

iogann1982 [59]

H+= 10^-14 / [OH-1 = 3.125 * 10^-4 M
pH=-log(H+) = 3.505

Just round it down and your answer = 3.5

3 0

2 years ago

Which law explain why tire pressure increases on a summer day

Musya8 [376]

Boyle's law

I hope this helps

3 0

3 years ago

Convert 99 moles of CO2 to atoms

lorasvet [3.4K]

Answer:

1.78 × 10²⁶ Atoms

Explanation:

Relation between number of molecules and moles is,

No. of Molecules = Moles × 6.022 × 10²³ Molecules/mol

No. of Molecules = 99 mol × 6.022 × 10²³ Molecules/mol

No. of Molecules = 5.96 × 10²⁵ Molecules

Also, In CO₂ Molecule there are 3 atoms.

So,

No. of atoms = 5.96 × 10²⁵ Molecules × 3

No. of atoms = 1.78 × 10²⁶ Atoms

3 0

2 years ago

Two aircraft rivets, one iron and the other copper, are placed in a calorimeter that has an initial temperature of 20.°C. The da

Igoryamba

The heat will flow from Cu to Fe because Cu has higher temperature and has lower peak value .

Given ,

two aircraft rivets , one iron and the other copper , are placed in a calorimeter .

the initial temp of the calorimeter is 20 degC .

mass of iron = 30 g

initial temp of iron = 0 degC

Mass of copper = 20 g

initial temp of copper = 100 degC

Here copper has higher temp ,thus heat flow from Cu to Fe .

Heat flow is the movement of heat from higher temperature to lower temperature .

<h3>What is calorimeter ?</h3>

It is an object used for measuring the heat flow , heat capacity of a chemical reaction as well as the physical changes .

Learn more about calorimeter here :

brainly.com/question/1407669

#SPJ4

8 0

1 year ago

Select the equations below that represent physical changes.

Ierofanga [76]

Physical changes- any change in the physical properties of the substance is a physical change. Generally physical properties include color, state, size , shape, odour, appearance . In any phyical change, no new substance is formed.

Chemical changes- any change in the chemical properties of the substance is a chemical change. Chemical properties changes only when something new is formed during a reaction.

∴ <u>Part A</u>- 2 H2O(l) → 2 H2(g) + O2(g)

In this, H2 and O2 is produced during the reaction which is different from H20. Thus, it is a chemical change.

<u>Part B</u>- H2O(l) → H2O(s)

In this, only the state of water changes from liquid to solid and no new product is formed. Thus, it is a physical change.

<u>Part C</u><u>-</u>CO2(s) → CO2(g)

In this also, only the state of CO2 changes from solid to gas and no new product is formed. Thus, it is a physical change.

<u>Part D-</u>H2(g) → 2 H(g)

In this reaction, H2 molecule is dissociated into 2 hydrogen atom leading to formation of new products. Thus, it is a chemical change.

Finally, equations that represent physical changes are - B and C

B. H2O(l) → H2O(s)

C. CO2(s) → CO2(g)

6 0

3 years ago