Answer:
Explanation:
1.Scientists use a shared system for reporting measurements called the International System of Units (SI). We use common measurement systems because science involves a lot of replication to confirm results. The most common system used in science is the metric system.
2.m, kg, m^3
3. g value change
Evaporation!
-Melting is a solid to a liquid
-sublimation is directly from a solid to a gas
-condensation gas to liquid
Zeff is the effective nuclear charge wherein, Z resembles the number of protons in the nucleus while S corresponds to the number of non-valence electrons.
Zeff = Z - S
Silicon has 14 protons; its electron configuration is [Ne] 3s2 3p2. Its
non-valence electrons is in the n = 1 and n =2 shells. There are 2
electrons in n = 1 and 8 in n = 2, so there are a total of 10
non-valence electron.
<span><span>Z<span>eff</span></span>= 14−10= 4</span>
So, the answer is 4.
Answer:
Other substances that give a positive test with AgNO3 are other chlorides present, iodides and bromide. However iodides and bromides have different colours hence they will not give a false positive test for KCl. Other chlorides present may lead to a false positive test for KCl.
Explanation:
In the qualitative determination of halogen ions, silver nitrate solution is used. Various halide ions give various colours of precipitate with silver nitrate. Chlorides yield a white precipitate, bromides yield a cream precipitate while iodides yield a yellow precipitate. All these ions or some of them may be present in the system.
However, if other chlorides are present, they will also yield a white precipitate just as KCl leading to a false positive test for KCl. Since other halogen ions yield precipitates of different colours, they don't lead to a false test for KCl. We can exclude other halides from the tendency to lead us to a false positive test for KCl but not other chlorides.
