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".
Answer:
The products are Al(NO₃)₃(aq) and H₂(g).
Al(s) + 3 HNO₃(aq) ⇒ Al(NO₃)₃(aq) + 1.5 H₂(g)
Explanation:
Let's consider the reaction between aluminum and nitric acid. This is a single replacement reaction, in which Al replaces H in HNO₃ to form aluminum nitrate. The unbalanced reaction is:
Al(s) + HNO₃(aq) ⇒ Al(NO₃)₃(aq) + H₂(g)
We start balancing N atoms by multiplying HNO₃ by 3.
Al(s) + 3 HNO₃(aq) ⇒ Al(NO₃)₃(aq) + H₂(g)
Finally, we get the balanced equation multiplying H₂ by 1.5.
Al(s) + 3 HNO₃(aq) ⇒ Al(NO₃)₃(aq) + 1.5 H₂(g)
Answer:RDA: The Recommended Dietary Allowance (RDA) for adults 19-51+ years is 400-420 mg daily for men and 310-320 mg for women. Pregnancy requires about 350-360 mg daily and lactation, 310-320 mg.
Explanation:
Answer is: mass of HCl is 15,6 g.
Chemical reaction: Mg + 2HCl → MgCl₂ + H₂.
m(Mg) = 5,2 g.
n(Mg) = m(Mg) ÷ M(Mg).
n(Mg) = 5,2 g ÷ 24,3 g/mol.
n(Mg) = 0,213 mol.
From chemical reaction: n(Mg) : n(HCl) = 1 : 2.
n(HCl) = 0,426 mol.
m(HCl) = 0,426 mol · 36,45 g/mol.
m(HCl) = 15,6 g.
