Answer:
The hydrogen gas is prepared in the laboratory required zink granules, dilute sulphuric acid or dilute hydrogen chloride, flask or woulfe’s bottle, and thistle funnel. by the downward displacement of water because it is a gas lighter than water
Reaction:
Zn (s)+2HCl (aq) →ZnCl2(aq)+H2(g)
Zn (s)+H2SO4(aq)→ZnSO4(aq)+H2(g)
The zinc granules are taken in a flask or Woulfe’s bottle and It is connected with the delivery tube to a water trough containing water. Dilute sulphuric acid is poured slowly from the thistle funnel. The hydrogen gas is released and collected in a gas jar by by the downward displacement of water as H2 gas lighter than water
Answer:
The mountains and water made travelling
diffucult but the Greeks were able to overcome it
Explanation:
i only know this bc im greek
A net population decline resulting from an "excess of deaths over births".
Option: A
<u>Explanation</u>:
Demographic transition is a shift from higher to lower level of fertility and mortality.Rapid development in industrialization and urbanization in 
century resulted into enormous population growth. But decline in early 
century covered many reasons like consequences of two calamitous wars, where Europe suffered large population declination due to battle death and civilian causalities in World War I and II. Hence the acceleration of population growth in 19th century but downfall in 20th is also considered as balance.
Answer:
sorry if its too big.
Explanation:
U.S. immigration has occurred in waves, with peaks followed by troughs (see figure). The first wave of immigrants, mostly English-speakers from the British Isles, arrived before records were kept beginning in 1820. The second wave, dominated by Irish and German Catholics in the 1840s and 1850s, challenged the dominance of the Protestant church and led to a backlash against Catholics, defused only when the Civil War practically stopped immigration in the 1860s.
The third wave, between 1880 and 1914, brought over 20 million European immigrants to the United States, an average of 650,000 a year at a time when the United States had 75 million residents. Most southern and eastern European immigrants arriving via New York’s Ellis Island found factory jobs in Northeastern and Midwestern cities. Third-wave European immigration was slowed first by World War I and then by numerical quotas in the 1920s.
Between the 1920s and 1960s, immigration paused. Immigration was low during the Depression of the 1930s, and in some years more people left the United States than arrived. Immigration rose after World War II ended, as veterans returned with European spouses and Europeans migrated. The fourth wave began after 1965, and has been marked by rising numbers of immigrants from Latin America and Asia. The United States admitted an average 250,000 immigrants a year in the 1950s, 330,000 in the 1960s, 450,000 in the 1970s, 735,000 in the 1980s, and over 1 million a year since the 1990s.
Answer:
<u>In glaciers, North and South poles and some lakes.</u>
Explanation:
- As more than 70% of freshwater can be found in continental glaciers around the world. The rest is in icecaps and 0.5 % store in lakes and rivers, and swamps.
- Rest if possible may be found in the groundwater aquifers, hidden in remote and cut off lace of the world.
- Antarctica and arctic alone consist of a huge share of freshwater in the world which is stored in ice forms. While 97% of oceanic water is saline not fit for drinking.
- Various techniques are available for desalination of water but most of it not suitable for long term use. As it may have bacteria and harmful effects on the body. Due to climate change release of methane gas and other harmful greenhouse gases are quickly melting and depleting the freshwater r
