All categories

3 years ago

Here is my question only answer if you understand this question

Chemistry

1 answer:

sasho [114]3 years ago

8 0

1- false
2- true
3- true
4- false
5- true
6- false
7- true
8- true
9- true
10- false

Hope it helps :)

You might be interested in

with the help of balanced chemical equation explain what happens when zinc is put in dilute hydrochloric acid

blagie [28]

They react to form salt ZnCl + hydrogen gas

3 0

3 years ago

17, A compound is a substance composed of two or

Serhud [2]

Answer:

Explanation:

Wow

7 0

3 years ago

Read 2 more answers

Given the following data:

bagirrra123 [75]

$176.0 \; \text{kJ} \cdot \text{mol}^{-1}$

As long as the equation in question can be expressed as the sum of the three equations with known enthalpy change, its $\Delta H$ can be determined with the Hess's Law. The key is to find the appropriate coefficient for each of the given equations.

Let the three equations with $\Delta H$ given be denoted as (1), (2), (3), and the last equation (4). Let $a$ , $b$ , and $c$ be letters such that $a \times (1) + b \times (2) + c \times (3) = (4)$ . This relationship shall hold for all chemicals involved.

There are three unknowns; it would thus take at least three equations to find their values. Species present on both sides of the equation would cancel out. Thus, let coefficients on the reactant side be positive and those on the product side be negative, such that duplicates would cancel out arithmetically. For instance, $3 + (-1) = 2$ shall resemble the number of $\text{H}_2$ left on the product side when the second equation is directly added to the third. Similarly

$\text{NH}_4 \text{Cl} \; (s)$ : $-2 \; a = 1$
$\text{NH}_3\; (g)$ : $-2 \; b = -1$
$\text{HCl} \; (g)$ : $2 \; c = -1$

Thus

$a = -1/2\\b = 1/2\\c = -1/2$ and

$-\frac{1}{2} \times (1) + \frac{1}{2} \times (2) - \frac{1}{2} \times (3)= (4)$

Verify this conclusion against a fourth species involved- $\text{N}_2 \; (g)$ for instance. Nitrogen isn't present in the net equation. The sum of its coefficient shall, therefore, be zero.

$a + b = -1/2 + 1/2 = 0$

Apply the Hess's Law based on the coefficients to find the enthalpy change of the last equation.

$\Delta H _{(4)} = -\frac{1}{2} \; \Delta H _{(1)} + \frac{1}{2} \; \Delta H _{(2)} - \frac{1}{2} \; \Delta H _{(3)}\\\phantom{\Delta H _{(4)}} = -\frac{1}{2} \times (-628.9)+ \frac{1}{2} \times (-92.2) - \frac{1}{2} \times (184.7) \\\phantom{\Delta H _{(4)}} = 176.0 \; \text{kJ} \cdot \text{mol}^{-1}$

3 0

3 years ago

In the reaction Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq), how many moles of hydrogen gas will be produced from 250.0 milliliters of

satela [25.4K]

Mg + 2HCl = H₂ + MgCl₂

n(HCl)=c(HCl)v(HCl)

n(H₂)=n(HCl)/2=c(HCl)v(HCl)/2

n(H₂)=3.0mol/L*0.2500L/2=0.375 mol≈0.38 mol

5 0

3 years ago

Read 2 more answers

Elements within the same group of the periodic table behave similarly because they have the same number of ?

sammy [17]

The elements in each group have the same number of electrons in the outer orbital. Or also called valence electrons. Khan academy has a great video online explaining why this happens. (It only happens for main group elements). Here is a link (sorry you can’t click it in Brainly) https://www.khanacademy.org/science/chemistry/periodic-table/copy-of-periodic-table-of-elements/v/periodic-table-valence-electrons. Feel free to message me for a better explanation, I would explain now but I’m not sure how much you know about this. If you know how to write an electron configuration you can see how all the electron configurations for the same group (not the transitional metals only the main groups) have the same number of valence electrons. I hope that helped, sorry I was vague about the explanation :)

4 0

3 years ago

Here is my question only answer if you understand this question​

Here is my question only answer if you understand this question