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3 years ago

In your own words, define:

Chemistry

1 answer:

vodomira [7]3 years ago

8 0

Hey there!

1.)

The law of conservation of mass states that matter cannot be created or destroyed. This means in a chemical reaction, the products must be equal to the reactants.

2.)

In a balanced chemical equation, there are the same amount of each type of atom, or element, on each side. The products must be equal to the reactants to follow the law of conservation of mass.

3.)

When a chemical reaction occurs, we can see evidence such as bubbles, odor, color change, and heat/light being released. These all are signs that a new substance is being formed.

Hope this helps!

You might be interested in

John dissolves .5g of a white powder in 25g of benzene (FP 5oC) (kf benzene is 5.1) and finds the solution freezes at 3.7oC. Det

navik [9.2K]

Answer:

The compound has a molar mass of 78.4 g/mol

Explanation:

Step 1: data given

Mass of a sample = 0.5 grams

Mass of benzene = 25 grams

Freezing poing = 5 °C

Kf of benzene = 5.1 °C/m

Freezing point solution = 3.7 °C

Step 2: Calculate molality

ΔT = i*Kf*m

⇒with ΔT = the freezing point depression = 5.0 - 3.7 = 1.3 °C

⇒with i = the can't hoff factor = 1

⇒with Kf = the freezing point depression constant of benzene = 5.1 °C/m

⇒with m = the molality

1.3 = 5.1 * m

m = 1.3 / 5.1

m = 0.255 moles /kg

Step 3: Calculate moles

Molality = moles / mass benzene

0.255 molal = moles / 0.025 kg

Moles = 0.255 molal * 0.025 kg

Moles = 0.006375 moles

Step 4: Calculate molar mass of the compound

Molar mass compund = mass / moles

Molar mass compound = 0.5 grams / 0.006375 moles

Molar mass compound = 78.4 g/mol

The compound has a molar mass of 78.4 g/mol

7 0

3 years ago

please answer the last points i have

Reil [10]

i think it is the cell wall.

6 0

3 years ago

Why is the Chemical symbol for lead Pb?? ^__^ i HATE the perdiotic** table!!

tatuchka [14]

Cause latin name of Pb is plumbum.
The same K - potassium - latin name is kalium.

3 0

3 years ago

In which reaction does the oxidation number of hydrogen change? In which reaction does the oxidation number of hydrogen change?

dedylja [7]

Answer: The correct answer is $2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq.)+H_2(g)$

Explanation:

Oxidation number is defined as the number which is given to an atom when it looses or gains electron. When an atom looses electron, it attains a positive oxidation state. When an atom gains electron, it attains a negative oxidation state.

Oxidation state of the atoms in their elemental state is considered as 0. Hydrogen is present as gaseous state.

For the given chemical reactions:

Reaction 1: $2HClO_4(aq.)+CaCO_3(s)\rightarrow Ca(ClO_4)_2(aq.)+H_2O(l)+CO_2 (g)$