Answer:
Su fórmula molecular es Na Cl y es el producto de la base hidróxido sódico (NaOH) y ácido clorhídrico, H Cl. En general, las sales son compuestos iónicos que forman cristales. Son generalmente solubles en agua, donde se separan los dos iones. Las sales típicas tienen un punto de fusión alto, baja dureza, y baja compresibilidad.
Explanation:
A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance
Any substance that accept a proton by definition is considered to be BRONSTED LOWRY BASE.
Bronsted Lowry defined acid and base on the basis of donating or accepting protons. In the Bronsted Lowry classification of acid and base, an acid is defined as a substance which donate proton while a base is defined as a substance which accept proton.
Answer:

Explanation:
The unbalanced nuclear equation is

Let's write X as a nuclear symbol.

The main point to remember in balancing nuclear equations is that the sums of the superscripts and of the subscripts must be the same on each side of the reaction arrow.
Then
235 = 4 + A , so A = 235 - 4 = 231, and
92 = 2 + Z , so Z = 92 - 2 = 90
And your nuclear equation becomes

Element 90 is thorium, so

Answer:
There are 2 hydrogen atoms, one magnesium atom, and 5 atoms in total.
Explanation:
We are given a compound in formula form. To make things easier to understand, we can first convert this to the name of the compound.
- When a compound contains one or more elements in parentheses, these are usually a <u>polyatomic ion</u>.
- Polyatomic ions are ions made up of two or more elements with a positive or negative charge over the entire ion. Commons examples of these NH₄⁺ (ammonia) and HCO₃⁻ (bicarbonate).
- You can combine metals with polyatomic ions to create commonly known compounds, such as baking soda. The chemical name for baking soda is sodium bicarbonate, so we can combine Na (sodium) with HCO₃⁻ (bicarbonate) and create sodium bicarbonate: NaHCO₃.
This compound is one magnesium atom bonded to two hydroxide ions.
- Hydroxide is the compound between one hydrogen atom and one oxygen atom. The compound overall adopts a negative charge of 1.
- If we have one hydrogen atom and one oxygen atom, the most electronegative atom is written first in chemical formulas. Therefore, the symbol for Oxygen (O) goes first.
- Then, write in the hydrogen atom directly after the O symbol: OH.
- Finally, since we have a negative charge on the ion, we need to play a negative sign as a superscript for the compound. Therefore, this becomes OH⁻.
Now, we need to determine the charge on the Magnesium atom which is determined from the amount of valence electrons the atom has.
- On a periodic table, the symbol for Magnesium is Mg and this element has 2 valence electrons.
- In order to fulfill the Octet Rule, the It is more likely to give up 2 electrons to a nonmetal than it is to gain 6, so we can safely assume that the charge is ²⁺.
- We need to use the criss-cross technique to transfer the charges between the element and the ion, so the negative 1 charge goes to the Mg, which does not appear (negative 1 or positive 1 are implied) and since the magnesium has a charge of positive 2, this is the subscript for the hydroxide ion.
- Therefore, our compound becomes Mg(OH)₂, and we have labeled this as magnesium hydroxide.
Now, to the number of atoms:
- The new charge on Mg is 1-, so there is only one atom of Mg.
- The charge is 2+ on the OH ion, so there are two atoms of H and two atoms of O.
- Two atoms of oxygen, two atoms of hydrogen, and one atom of magnesium add up to be five atoms in total.