What scientist use the scientific method to determine if cold was a substance?

dlinn [17]

Answer:

See the answer and the resolution below

Explanation:

The equation of the decomposition of magnesium carbonate is as follows:

Mg C03 (white solid) ---> C02 (gas) + Mg= (solid)

To calculate the mass of carbon dioxide produced, the weight of 1 mol of this and 1 mol of MgC03 is calculated. Then a simple rule of 3 is made.

Weight 1 mol of MgC03= Weight Mg + Weight C+ 3x(Weight 0)= 24,305g+ 12,017+3x (15,999)= 84, 318g/mol

Weight 1 mol of C02= Weight C + 2x(Weight 0)=12,017+2x (15,999)= 44, 008g/mol

84, 319 g MgC03------44,008g C02

36,0 g MgC03------X= (36,0 g MgC03x44,008g C02)/84, 319 g MgC03= 18,8 g C02

3 0

4 years ago

Calculate the concentration of hydronium and hydroxide ions in a 0.050 M solution of nitric acid.

Mazyrski [523]

Answer:

[H₃O⁺] = 0.05 M & [OH⁻] = 2.0 x 10⁻¹³.

Explanation:

HNO₃ is completely ionized in water as:

HNO₃ + H₂O → H₃O⁺ + NO₃⁻.

The concentration of hydronium ion is equal to the concentration of HNO₃:

[H₃O⁺] = 0.05 M.

∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.

∴ [OH⁻] = 10⁻¹⁴/[H₃O⁺] = 10⁻¹⁴/0.05 = 2.0 x 10⁻¹³.

3 0

3 years ago

what are the mole ratios of hydrazine (n2h4) to hydrogen peroxide (h2o2) and hydrazine to water? 1:2 and 1:4 1:3 and 1:4 1:2 and

Shalnov [3]

To determine the mole ratios of the substances, we need to know the balanced chemical reaction of the system. The reaction between hydrazine and hydrogen peroxide yields to nitrogen and water. The balanced chemical reaction is:

N2H4 + 2H2O2 --> N2 + 4H2O

Therefore, the mole ratio between hydrazine and hydrogen peroxide is 1:2 and the mole ratio between hydrazine and water is 1:4.

3 0

3 years ago

A sample of a gas occupies 2.76 L at 303K. What would the volume be if the temperature was increased to 404K? Assume constant

Artist 52 [7]

Answer:

If the temperature was increased to 404 K, its volume would be 3.68 L.

Explanation:

Charles' Law gives a relationship between the volume and the temperature of the gas at constant temperature. This law states that the volume of a given amount of gas held at constant pressure is directly proportional to the temperature.

$V\propto T$

$\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}$

Let

$V_1=2.76\ L\\\\T_1=303\ K\\\\T_2=404\ K$

Let $V_2$ is new volume. Using above formula we get :

$V_2=\dfrac{V_1T_2}{T_1}\\\\V_2=\dfrac{2.76\times 404}{303}\\\\V_2=3.68\ L$

If the temperature was increased to 404 K, its volume would be 3.68 L.

6 0

4 years ago

How does the plum-pudding model illustrate the atom’s structure?

Westkost [7]

Answer:

The plum-pudding model proposed that an atom is composed of negatively-charged particles floating within a sea of positive charges. This sea of positive charges served to counterbalance the negative charge on the electrons so that the atom remains neutral.

Explanation:

J.J. Thompson from experiments he conducted with the rays produced from a cathode tube to which a high voltage is applied across its two ends, discovered that these rays were negatively charged and had a mass much much smaller than the mass of any known atom. These negatively-charged rays were later called electrons. Since the atom was neutral in charge overall, J.J. Thompson then proposed the plum-pudding model.

The plum-pudding model proposed that an atom is composed of negatively-charged particles floating within a sea of positive charges. This sea of positive charges served to counterbalance the negative charge on the electrons so that the atom remains neutral. The name of this model was chosen because it resembled the English dessert, plum-pudding.

3 0

3 years ago