All categories

3 years ago

Just a curious question to the Chemists,

Chemistry

1 answer:

Vikki [24]3 years ago

8 0

Answer:

well the world would be shocked

Explanation:

and suprise

You might be interested in

12.<br> An object with a mass of 3 kg has a momentum of 75 kg•m/s. What is the velocity?

marissa [1.9K]

Answer:

the velocity is 25 m/s

Explanation:

The computation of the velocity is shown below:

As we know that

Magnitude of Momentum = (mass) × (speed)

75 kg. m/s = 3 kg × speed

So, the speed is

= 75 ÷ 3

= 25 m/s

hence, the velocity is 25 m/s

3 0

2 years ago

The combustion of ethene in the presence of excess oxygen yields carbon dioxide and water: c2h4 (g) + 3o2 (g) → 2co2 (g) + 2h2o

meriva

Answer:

$\boxed{-267.5}$

Explanation:

You can calculate the entropy change of a reaction by using the standard molar entropies of reactants and products.

The formula is

$\Delta_{r} S^{\circ} = \sum_n {nS_{\text{products}}^{\circ} - \sum_{m} {mS_{\text{reactants}}^{\circ}}}$

The equation for the reaction is

C₂H₄(g) + 3O₂(g) ⟶ 2CO₂(g) + 2H₂O(ℓ)

ΔS°/J·K⁻¹mol⁻¹ 219.5 205.0 213.6 69.9

$\Delta_{r} S^{\circ} = (2\times213.6 + 2\times69.9) - (1\times219.5 + 3\times205.0)\\\\= 567.0 - 834.5 = \boxed{-267.5 \text{ J}\cdot\text{K}^{-1} \text{mol}^{-1}}$

3 0

3 years ago

An atom has a mass number of 25 and 13 neutrons. what is the atomic number of this atom? express your answer as an integer.

Snowcat [4.5K]

13 because an atom has the same number of protons as neutrons

5 0

2 years ago

If this decay has a half life of 2.60 years, what mass of 72.5 g of sodium 22 will remain after 15.6 years

Vlad1618 [11]

Sodium-22 remain : 1.13 g

<h3>Further explanation </h3>

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.

Usually, radioactive elements have an unstable atomic nucleus.

General formulas used in decay:

$\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{T/t\frac{1}{2} }}}$

T = duration of decay

t 1/2 = half-life

N₀ = the number of initial radioactive atoms

Nt = the number of radioactive atoms left after decaying during T time

half-life = t 1/2=2.6 years

T=15.6 years

No=72.5 g

$\tt Nt=72.5.\dfrac{1}{2}^{15.6/2.6}\\\\Nt=72.5.\dfrac{1}{2}^6\\\\Nt=1.13~g$

8 0

3 years ago

Methane (CH4) burns in oxygen to produce carbon dioxide and water. Which reaction is occurring here?

dusya [7]

It is a combustion reaction because when methane burns with oxyzen it produces carbon dioxide,water and heat and light.

8 0

3 years ago