Answer:
The answer to your question is: letter A
Explanation:
a) A + B ⇒ AB + heat It is an exothermic reaction because heat is released.
b) A + BΔ ⇒ AB It heat added to the reactants , then it is an endothermic reaction.
c) heat + BC ⇒ B + C It's an endothermic reaction because heat is added to the reactants.
d) B + heat + CD ⇒ BD + C It's and endothermic reaction because heat is added to the reactants.
Answer:
You cannot make observations if you are 57 seconds late into the lab.
Explanation:
The atomic nucleus can split by decay into 2 or more particles as a result of the instability of its atomic nucleus due to the fact that radioactive elements possess an unstable atomic nucleus.
Now, the primary particles which are emitted by radioactive elements in order to make them decay are alpha, beta & gamma particles.
The half life equation is;
N_t = N₀(½)^(t/t_½)
Where:
t = duration of decay
t_½ = half-life
N₀ = number of radioactive atoms initially
N_t = number of radioactive atoms remaining after decay over time t
We are given;
t = 57 secs
N₀ = 100 g
Now, half life of Nitrogen-16 from online sources is 7.2 seconds. t_½ = 7.2
Thus;
N_t = 100(1/2)^(57/7.2)
N_t = 0.4139g
We are told that In order to make observations, you require at least .5g of material.
The value of N_t you got is less than 0.5g, therefore you cannot make observations if you are 57 seconds late.
Answer:
1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3
Explanation:
Benzene is a stable aromatic compound hence it undergoes substitution rather than addition reaction.
When benzene undergoes substitution reaction, the substituent introduced into the ring determines the position of the incoming electrophile.
If I want to synthesize m-nitropropylbenzene, I will first carry out the nitration of benzene using HNO3/H2SO4 since the -nitro group is a meta director. This is now followed by Friedel Craft's alkykation using CH3CH2CH2Cl/AlCl3.
The masses of the liquids are different making them have different densities
Answer:
0.350 g of iron
Explanation:
Step 1: Given data
Mass of iron (m): 350 mg
Step 2: Convert the mass of iron to milligrams
In order to convert the mass of iron from grams to milligrams we need a conversion factor. In this case, the conversion factor is 1 g = 1,000 mg.
350 mg Fe × 1 g Fe/1,000 mg Fe = 0.350 g Fe
350 milligrams of iron is equal to 0.350 grams of iron. We conserve the 3 significante figures of the original data.