Answer:
NH4Cl, NaCl, Ba(OH)2, NaOH
Explanation:
NH4Cl is an acidic salt formed by the neutralization of a strong acid (HCl) with a weak base (NH3). Hence, it will habe a PH<7 (the lowest PH).
NaCl is a neutral salt,formed by neutralization of a strong acid (HCl) with a strong base (NaOH). Hence, it will have a PH of 7.
Ba(OH)2 is a weak base. Therefore, it will have a PH between 8 and 10.
NaOh meanwhile, is a strong base. Therefore, it will have a PH between 10 to 13.
Hence, we have
NH4Cl < NaCl < Ba(OH)2 < NaOH
Answer:
c
Explanation:
1. litmus paper is used when showing a change between a greater range in ph levels - so A and D are automatically a no.
2. methyl red is used to show a range in ph levels between 4.8-6
3. Option C is the only one left so im going to assume its C because its definitely not A, B, or D
Answer:
a) Step 1:

Step 2:

b) The overall balanced reaction for given process is ;

Explanation:
a)
Galena = 
Lead(II) oxide = 
Sulfur dioxide = 
Step 1:
Roasting the galena in oxygen gas to form lead(II) oxide and sulfur dioxide.
Balanced equation of step 1:
..[1]
Step 2:
Heating the metal oxide with more galena forms the molten metal and more sulfur dioxide.
Balanced equation of step 2:
..[2]
b)
For over all reaction add [1] and [2]. The overall balanced reaction for given process is ;

Answer:

Explanation:
The atomic number (Z) of copper is 29 and this isotope has an atomic mass (A) of 70.
The general symbol for an isotope E is
.
The atomic number is a left subscript, and the atomic mass is a left superscript.
