Because where it is hot there will be more water because it won't freeze.
chemical weathering occurs more quickly in a HOT and HUMID environment but the effect of temperature on weathering is hard to quantify. Generally, chemical reaction rates are approximately doubled with a 10 C increase in temperature. In addition, water plays an important role in every aspect of chemical weathering. Hence the humid and hot climate.
Chemical weathering occurs more quickly in a hot climate because where it is hot there will be more water because the won't freeze.
because of the dry weather.
it happens because certain types of rocks like granite crumble easier in hot weather, but stays hard in cold weather.