Answer:
+1
Explanation:
A Potassium atom is represented with the sign "K" in chemistry and have atomic number 19.
The charge of electrons causes a matter to experience a force and it can be positive or negative.
In Potassium atom, the electric charge is +1 to enter a stable electron configuration as there is only one valence electron in the outermost shell of potassium atom. As potassium atom will lose electron it will become positively charged.
Hence, the correct answer is "+1".
- Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH)2. It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (Ksp = 5.61×10−12). Magnesium hydroxide is a common component of antacids, such as milk of magnesia.
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Missing text find on internet: a<span> 90,0 mL sample of water is heated to its boiling point.
V(H</span>₂O) = 90,0 mL.
d(H₂O) = 1,00 g/mL.
m(H₂O) = 90 mL · 1,00 g/mL.
m(H₂O) = 90 g.
n(H₂O) = m(H₂O) ÷ M(H₂O).
n(H₂O) = 90 g ÷ 18 g/mol.
n(H₂O) = 5 mol.
Q = n(H₂O) · ΔHvap
Q = 5 mol · 40.65 kJ/mol.
Q = 203,250 kJ.
Q - heat reqiured.
Part 1: Potassium, and Rubidium.Part 2: Calcium has 20 protons and 20 electrons because the atomic number for calcium is 20 and that determines how many protons there are and in an atom, the number of protons is the same number of electrons. Calcium has about 20 neutrons. I got the number of Neutrons by subtracting the mass number(40.078) and the atomic number(20), I got 20.078. Round to the nearest whole number because you cannot have half or partial neutron. So, Calcium has 20 protons, 20 electrons, and 20 neutrons,
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