I am not sure about .030 but i would pick c
.025) b
26)c
27)d
28)d
Answer:
The answer is 1.06g.
Explanation:
Analysis of question:
1. Identify the information in the question given.
- volume of HCl is 2 dm3
- pH of HCl is 2.0
2. What the question want?
- mass of Na2CO3 is ?(unknown)
- 3. Do calculation.
- 1st-Write a balanced chemical equation:
Na2CO3 + 2HCl (arrow) 2NaCl + H20 + CO2
- 2nd-Determine the molarity of HCl with the value of 2.0.
pH= -log[H+]
2.0= -log[H+]
log[H+]= -2.0
[H+]= 10 to the power of negative 2(10-2)
=0.01 mol dm-3
molarity of HCl is 0.01 mol dm-3
- 3rd-Find the number of moles of HCl
n=MV
=0.01 mol dm-3 × 2 dm3
=0.02 mol of HCl
- 4th-Find the second mol of it.
Based on the chemical equation,
2.0 mol of HCl reacts with 1.0 mol of Na2CO3
0.02 mol of HCl reacts with 0.01 mol of Na2CO3
<u>N</u><u>a</u>2CO3>a=<u>1</u><u> </u>mol
<u>2</u><u>H</u>Cl>b=<u>2</u><u> </u>mol
mass= number of mole × molar mass
g=0.01 × [2(23)+ 12+ 3(16)]
g=0.01 × 106
# =1.06 g.
Answer:
The cow digestive system is not at all like the human digestive system. The main difference between the human digestive system and the cow's animal digestive system is simple: Cows have a stomach that consists of four compartments, commonly referred to as four stomachs. Cows spend the better part of the day eating, swallowing and regurgitating their food, and chewing it again before final digestion. Because a cow's teeth mostly grind their food, cows use their tongues – which is why they are so long – to help them gather and grasp grass for pinching off between their incisors and dental pad at the front part of their mouths.
Explanation:
Answer:
Anhydride, any chemical compound obtained, either in practice or in principle, by the elimination of water from another compound. Examples of inorganic anhydrides are sulfur trioxide, SO3, which is derived from sulfuric acid, and calcium oxide, CaO, derived from calcium hydroxide
Explanation:
<h3>
<em><u>examples</u></em><em><u>.</u></em></h3>
1)acid anhydride.
2)basic anhydrides.
<h3>
<em><u>reactions</u></em><em><u>. </u></em></h3>
1)reaction with water
(CH3CO)2O + H2O → 2 CH3CO2H.
Answer:
snail should be at the top
Explanation:
