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3 years ago

Evidence of chemical reactions include -

Chemistry

1 answer:

Ludmilka [50]3 years ago

6 0

Answer:

I think it's light production, color change (new/different), gas production (bubbles/fizzing - not boiling), precipitate, and temperature change

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Which is a diatomic molecule?<br><br> A) Ar<br> B) CO<br> C) CO2<br> D) NaCl

Alenkinab [10]

Answer:

I think it is c)co2

Explanation:

4 0

4 years ago

Read 2 more answers

One would not expect yeast to undergo fermentation in the presence of

Hunter-Best [27]

Answer:

Oxygen.

Explanation:

Hello,

Yeast fermentation in the food industry must be carried out under anaerobic conditions as long as when oxygen is present respiration occurs rather than fermentation.

Best regards.

3 0

3 years ago

How many grams of MgCO3 are required to neutralize 200. mL of stomach acid HCl, which is equivalent to 0.0465 MHCl?

tester [92]

<h3>Answer:</h3>

0.392 g

<h3>Explanation:</h3>

We are given the following;

Volume of HCl is 200 mL

Molarity of HCl is 0.0465M

We are required to calculate the mass of MgCO₃ required

<h3>Step 1: Write the balanced equation for the reaction </h3>

The balanced equation for the reaction is;

MgCO₃(s) + 2HCl(aq) → MgCl₂(aq) + CO₂(g) + H₂O(l)

<h3>Step 2: Calculate the moles of HCl</h3>

When given the molarity of a compound and the volume, the number of moles can be calculated by;

Number of moles = Molarity × Volume

Therefore;

Volume of HCl = 0.0465 M × 0.2 L

= 0.0093 moles

<h3>Step 3: Calculating the number of moles of MgCO₃</h3>

From the equation, one mole of MgCO₃ reacts with two moles of HCl

Therefore, the mole ratio of MgCO₃ : HCl is 1 : 2

Hence, moles of MgCO₃ = Moles of HCl ÷ 2

= 0.0093 moles ÷ 2

= 0.00465 moles

To calculate the mass of a compound we need to multiply the molar mass of a compound with the number of moles.

Molar mass of MgCO₃ is 84.314 g/mol

Thus, Mass of MgCO₃ = 0.00465 moles × 84.314 g/mol

= 0.392 g

Therefore, 0.392 g of MgCO₃ are required to neutralize the acid.

3 0

4 years ago

Three moles of oxygen gas is stored in a 2.5-liter container at 35°C. What is the pressure of this gas?

nadezda [96]

Answer:

The pressure of the gas is 30.3072 atm.

Explanation:

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P * V = n * R * T

In this case: