Answer:
B) a substance's color and odor changed Explanation: A signal that a chemical change has occurred is when its odor (its smell) or its appearance has changed.
Answer:
Aluminum is ideal for aircraft manufacture because it's lightweight and strong. Aluminum is roughly a third the weight of steel, allowing an aircraft to carry more weight and or become more fuel efficient. Furthermore, aluminum's high resistance to corrosion ensures the safety of the aircraft and its passengers.
Explanation:
What is the problem u need help with
The molecular weight of hemoglobin can be calculated using osmotic pressure
Osmotic pressure is a colligative property and it depends on molarity as
πV = nRT
where
π = osmotic pressure
V = volume = 1mL = 0.001 L
n = moles
R = gas constant = 0.0821 L atm / mol K
T = temperature = 25°C = 25 + 273 K = 298 K
Putting values we will get value of moles

we know that

Therefore

Answer:
For eacht 4 moles Fe consumed, we will produce 2 moles Fe2O3
The mole ration is 4:2 (option 1)
Explanation:
Step 1: The unbalanced equation
Fe + O2 → Fe2O3
Step 2: Balancing the equation
Fe + O2 → Fe2O3
On the left side we have 2x O (in O2) and on the right side we have 3x O (in Fe2O3) . To balance the amount of O on both sides, we have to multiply O2 by 3 and Fe2O3 by 2.
Fe + 3O2 → 2Fe2O3
On the left side we have 1x Fe, On the right side we have 4x (in 2Fe2O3). To balance the amount of Fe we have to multiply Fe (on the left side) by 4.
Now the equation is balanced.
4Fe + 3O2 → 2Fe2O3
For eacht 4 moles Fe consumed, we will produce 2 moles Fe2O3
The mole ration is 4:2 (option 1)