Answer:
C
Explanation:
The battery is chemical energy. When it is used in the flashlight, it produces light and thermal energy
PLZ MARK BRAINLIEST :)
Answer: Strictly a laboratory analysis and can only be done using the data obtained during analysis
Explanation:
To find a solution to this problem, you need to use the data collected during the lab work. A guide could be finding the possible forms of hydrated copper chlorides in reference books. Since it's also a lab work, you can definitely compare your data with lab mates.
The formula CuxCly.zH₂O and its name chloride hydrate already gives you an idea of the possibilities of the value of the integers, hence you can take a good guess for the identity of the unknown salt and calculate the theoretical formular weight for it. From the that you can proceed to also find the mass of water and copper from your lab analysis.
Answer:
2100g or 2.1kg
Explanation:
Based on the equation given,
One mole of Fe2O3 gives two moles of Fe
Molar mass for Fe2O3 is 160g/mol
Molar mass for two Fe is 112g/mol
Convert 3kg to gram
3×1000=3000grams
160g of Fe2O3-112 g of Fe
3000g of Fe2O3-xg of Fe
Xg=3000×112/160
Xg=2100g
To convert to kg
2100/1000=2.1kg
Mass of Fe is 2.1kg
1. Write out the formula
Pb(NO3)2 (aq) + 2HCl (aq) ----> PbCl2 + 2HNO3
2. Use solubility guidelines (gotta memorize 'em) for the products to see if a solid forms
Nitrates are always soluble so 2HNO3 (aq)
Chlorides (Cl) are always soluble except for when you mix them with copper, lead, mercury, or silver.
Since you mixed it with lead (Pb) it is solid and forms a precipitate. PbCl2 (s)
Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
6. Sodium salicylate is made from carbon dioxide and sodium phenoxide.
The reactants are:
Carbon dioxide and sodium phenoxide
The product is:
Sodium salicylate
